HISTORY149 - Daylight Savings Time

President Trump’s recent attempts to eliminate daylight savings time have resulted in Congressional action to implement his goal, although final resolution of this issue is far from determined.  After taking a quick look at the proposal, I discovered that there is a long, turbulent history on this topic - little known to me, and others I suspect.  So, this blog will cover the history of daylight savings time.

After a short introduction, I will discuss how ancient civilizations addressed the subject; early efforts to provide daylight savings time (DST); formal actions to adopt DST in the two world wars and the 1973 energy crisis; the turmoil between these historical periods; the special cases of Arizona, Hawaii, and U.S. territories; and finally, current efforts to change DST.

As usual, I will list my principal sources at the end.

 

Introduction

Daylight saving time (DST) is the practice of advancing clocks to make better use of the longer daylight available during summer by having darkness fall at a later clock time.  The current typical implementation of DST is to adjust clocks ahead of Standard Time by one hour in spring (or late winter), and to set clocks back by one hour in the autumn (or fall); hence the handy memory device:  "spring forward and fall back.”

Typical modern daylight saving time operation.

 

In 2026, less than 40% (about 70) of the world's countries observe DST, primarily in Europe and North America, with some countries observing it only in some regions.  The vast majority of the global community stays on Standard Time year-round, particularly in Africa, South Asia, and equatorial regions.   North and south of the tropics, daylight lasts longer in summer and is shorter in winter, with the effect becoming greater the farther one moves away from the equator.  DST is of little use for locations near the equator, because these regions see only a small variation in daylight over the course of the year. 

In the United States, DST is observed everywhere except most of the state of Arizona , the state of Hawaii, and the territories of the U.S.

For millennia, ancient civilizations have tried to take advantage of longer daylight in summer.  The innovative approach was to alter their daily schedule by systematically (during each day) changing the length of their clock hours according to the season.  The formalized practice of DST was first tested and widely adopted in the 20^th century, in times of world wars and energy crises - when there was a clear need to save energy (see below).  But, between these historical periods, the need for, and value of DST, was hotly debated, with several instances of abandoning DST.  Let’s take a look at this spotty history … that continues today.

 

Ancient Civilizations

Ancient civilizations like the Egyptians, Greeks, and Romans adjusted daily schedules according to available sunlight more flexibly than DST does today, dividing daylight into 12 hours regardless of the seasonal total length of daylight, so that each daylight hour became progressively longer during spring and summer, and shorter during autumn and winter.  

For example, ancient Romans kept time with water clocks that had different scales for different months of the year; at Rome's latitude.  Beside specialized internal scales, these water clocks used rotating cylindrical columns to adjust for seasonal daylight shifts.

An early 19^th-century illustration of an advanced water clock from the 3^rd century BC.  The constant flow of water into a chamber in the clock would slowly raise a float with a pointer, for example a small figurine with a stick.  The stick would point to the time as displayed on a column.  The hour markings around the column would reflect the clock time.  The float turned a gear system that slowly rotated the cylinder a tiny bit each day.  On this “calendar” cylinder, the horizontal lines representing summer daytime hours were drawn further apart as daylight increased.  Because the float rose at a steady or controlled pace, it took more time to reach a summer hour line than a winter hour line.

 

This general approach lasted until the 14^th century, when equal-length clock hours supplanted unequal ones, so civil time (public time in a region) no longer varied by season.  Until modern times, most approaches to capitalize on longer summer daylight involved voluntary schedule (time of day) changes for key operations or events. 

 

Early Daylight Savings Time Efforts

New Zealand entomologist George Hudson first proposed modern DST.  His shift-work job gave him spare time to collect insects and led him to value after-hours daylight.  In 1895, he presented a paper to New Zealand’s Wellington Philosophical Society proposing a two-hour daylight-savings shift, generating considerable interest.  He followed up with an 1898 paper, but no action was taken.

New Zealander George Hudson first proposed modern DST.

Many publications credit the first DST proposal to prominent English builder and outdoorsman William Willett, who independently conceived DST in 1907 during a pre-breakfast horse ride when he observed how many Londoners slept through a large part of a summer day.  Willett also was an avid golfer who disliked cutting short his round at dusk.  His solution was to advance the clock during the summer, and he published the proposal two years later.  The first Daylight Savings Bill was introduced to the British House of Commons on 12 February 1908.   A select committee was set up to examine the issue, but the bill did not become law, and several other bills failed in the following years.  Willett lobbied for the proposal in the UK until his death in 1915.

On May 1, 1908, the twin cities of Port Arthur and Fort William, Ontario, Canada, were the first cities in the world to enact (summer) DST, lasting until November 1, 1908.  This was followed by Orillia, Ontario, adopting DST from 1911 to 1912, but only locally, not nationally.

Note:  Before the establishment of time zones, there were more than 144 local times in North America.  The resulting time differences between adjacent towns and cities were not critical when it took days to travel from place to place.  But, with the proliferation of railroads, faster travel became possible across large geographies, and travelers could sometimes arrive at an earlier local time than they had departed.  Due to this lack of time standardization, train scheduling proved difficult to coordinate, resulting in missed connections and collisions.  As a result, starting in 1883, the major railroad companies began to operate on a coordinated system of four time zones.  On March 19, 1918, with the Standard Time Act, the U.S. officially adopted five time zones as the country entered World War I: the Eastern, Central, Mountain, Pacific, and Alaska zones, all of which are still in use today.  (The Hawaii-Aleutian Time Zone was added in 1900.  The Atlantic, Samoa, and Chamorro Zones were added later for U.S. territories and outlying possessions through various acts and Department of Transportation adjustments.)

Modern U.S. time zones. Note that most of Arizona does not observe DST (see below).

 

World War I and After

The first countries to adopt summer Daylight Savings Time nationally were those of the German Empire and its World War I ally Austria-Hungary, commencing on 30 April 1916, as a way to conserve coal that provided vital energy during wartime.  By shifting an extra hour of daylight into the evening, this reduced the public's need for artificial indoor lighting and electricity, redirecting those critical energy resources toward military factories and the war effort.  

Britain, most of its allies, and many European neutrals soon followed.  Russia and a few other countries waited until the next year. 

The United States adopted summer daylight savings in 1918, with the very same Standard Time Act, signed by President Woodrow Wilson, that established the first U.S. time zones.  DST was implemented as a wartime fuel-conservation measure in the interest of adding more daylight hours.

Poster extolling DST in World War I.

 

The law took effect on March 19, 1919, and moved clocks forward one hour to extend evening daylight and reduce coal usage for artificial lighting.  The plan was for DST to run each year from the last Sunday in March until the last Sunday in October.  But Congress ended the national program, over President Wilson's veto, after only seven months, on August 20, 1919, due to fierce public pushback, though some major cities kept the practice locally.

City dwellers, merchants, and factory operators favored the extra daylight for leisure and retail.  Farmers strongly opposed DST because agricultural work depended on the natural rising and setting of the sun rather than mechanical clocks, making the early morning shift disruptive.

Most jurisdictions abandoned summer DST in the years after the war ended in 1918, with exceptions including Canada, the United Kingdom, France, and Ireland. 

In the U.S., the repeal of DST turned timekeeping back to a fragmented local option where individual cities and states could choose whether or not to shift their clocks.  With federal rules gone, major financial hubs like New York City kept a local daylight saving schedule to align with European markets, while nearby rural communities stayed on standard time.

This patchy, state-by-state confusion persisted for decades until the federal government stepped back in during World War II.

 

World War II and After

In the U.S., year-round DST, or "War Time" DST was signed into law via congressional action on February 9, 1942 by President Franklin Roosevelt, just weeks after the attack on Pearl Harbor.  The continuous wartime measure advanced the country's clocks by one hour to conserve fuel, electricity, and promote national security, until it ended on September 30, 1945.

U.S. Congressional action on year-round DST for World War II.

 

Following the end of World War II, the U.S. federal government dropped all daylight saving requirements; authority over time reverted to local and state governments.  For the next two decades, DST became a chaotic local option, leading to a patchwork system where individual cities and states chose whether or not to change their clocks.  Many eastern states and major cities kept summer DST, while rural regions and other states stayed on Standard Time.  Railroad, bus, airline, and broadcasting companies faced massive scheduling headaches due to conflicting local start and end dates.

 

Uniform Time Act

To put an end to the clock chaos, by creating a predictable national schedule, the U.S. Congress finally passed the Uniform Time Act, signed by President Lyndon B. Johnson on April 13, 1966, which standardized daylight savings time.

President Lyndon Johnson signing the Uniform Time Act.

 

Motivated by transportation and broadcast improvements, this act mandated Standard Time within the existing time zones and established a permanent system of uniform summer DST, including the dates and times for twice yearly transitions - starting on the last Sunday of April and ending on the last Sunday of October.

State governments could not independently change time zones or the length of DST, but they could exempt themselves entirely.  Today, DST is observed uniformly across the nation except in most of Arizona, Hawaii, American Samoa, Guam, Northern Mariana Islands, Puerto Rico, and the Virgin Islands.  See below.

 

1973 Energy Crisis

To save fuel during the 1973 oil embargo, the U.S. enacted the Emergency Daylight Savings Time Energy Conservation Act, signed by President Richard Nixon, putting the nation on year-round daylight saving time starting January 6, 1974.

At first, 79% of Americans liked the idea of extra evening daylight.  But sunrises occurred as late as 9 a.m. in some northern and western regions, with children walking or waiting for buses in pitch darkness, leading to several tragic traffic accidents and student fatalities.  There were also complaints from working people commuting and starting their work day in darkness during the winter.  Public approval dropped to 42% by February 1974.

Students waiting for a bus in darkness during year-round DST in 1974.

 

President Gerald Ford signed a law ending year-round DST in October 1974.  The U.S. returned to Standard Time for the winter months, resuming summer DST in spring 1975.

An amendment to the Uniform Time Act in 1986 and the Energy Policy Act of 2005 moved the start and end windows of summer DST.  Since 2007, DST begins on the second Sunday of March and ends on the first Sunday of November.

 

DST Exceptions

Arizona, Hawaii, and U.S. territories opted out of DST because their geographic locations make shifting the clocks unnecessary or counterproductive.

Arizona tried DST in 1967, but dropped it by 1968, because summer temperatures were so high that an extra hour of evening sunshine meant air conditioning units had to run longer during the hottest parts of the day.  And with late sunsets, residents had to wait until past 9:00 PM for the heat to drop before going outside.  

An exception within the state: Located in northeastern Arizona, the Navajo Nation does observe DST because the reservation spans across Utah and New Mexico, and observing the change keeps their entire tribal lands on the same time.

The Navajo Reservation in northeastern Arizona chose to observe DST.

  

Hawaii, Puerto Rico, Guam, American Samoa, the Northern Mariana Islands, and the U.S. Virgin Islands sit close to the equator.  Day length changes very little between summer and winter in these tropical regions.  DST provides no meaningful benefit.

 

Current Efforts to Change DST

On July 14, 2026, the U.S. House of Representatives passed the Sunshine Protection Act by a 308–117 vote to make year-round DST permanent nationwide.  The bill now awaits action in the Senate and President Donald Trump’s signature, meaning clocks will still "fall back" one hour this November unless the Senate passes the measure.

The recent House vote marks the furthest a federal permanent, year-round-DST bill has advanced after years of stalled proposals.  The bill faces an uncertain, uphill path in the Senate, where previous bipartisan efforts have historically slowed down over debate on whether to adopt permanent DST or permanent Standard Time.  President Trump has actively urged lawmakers on social media to pass the bill so Americans can stop the "ridiculous, twice yearly production" of changing clocks.

Nearly 20 states (including Texas, Florida, Colorado, and California) have already passed contingency legislation or resolutions ready to enact year-round DST the moment Congress changes federal law.

Public opinion polls show growing fatigue with the twice-yearly clock change.  Recent national surveys indicate a majority of Americans favor ending the biannual switch, with preference leaning toward permanent Standard Time over permanent DST.

DST is still a very controversial subject.

 

Supporters of DST Argue:

Extra evening daylight gives families, joggers, and outdoor enthusiasts more opportunities for physical fitness after work or school.  People can enjoy outdoor social events after work or school before it gets dark.

DST boosts retail shops, restaurants, and tourism industries from customers having more time and light to go out after hours.

Extra ambient light during late-afternoon and early-evening commuting hours helps reduce street robberies and pedestrian accidents.

Detractors of DST Argue:

Modern data indicate that the traditional rationale for DST - primarily energy conservation - no longer yields substantial returns.

Major medical and sleep organizations argue that DST misaligns our social clocks (circadian rhythm) with natural solar time, increasing risks for chronic health and sleep problems.  This chronic mismatch is associated with higher rates of obesity, diabetes, and mood disorders.

Sunrises could vary late into the morning during winter months, creating hazardous early commutes.  Children walking to school or waiting for buses could do so in pitch-black morning conditions.

 

 

 

 

 Sources

My principal sources include: “Daylight Saving Time,” Wikipedia.com; “The History of Daylight Saving Time,” Colorado.edu; “History of Time Zones and Daylight Saving Time (DST),” bts.gov; plus, numerous other online sources, including answers to many queries using Google in AI-Mode.