Baker City is a city in and the county seat of Baker County, Oregon, United States. It was named after Edward D. Baker, the only U.S. Senator ever killed in military combat. The population was 9,828 at the 2010 census.
Platted in 1865, Baker City grew slowly in the beginning. A post office was established on March 27, 1866, but Baker City was not incorporated until 1874. Even so, it supplanted Auburn as the county seat in 1868. The city and county were named in honor of U.S. Senator Edward D. Baker, the only sitting senator to be killed in a military engagement. He died in 1861 while leading a charge of 1,700 Union Army soldiers up a ridge at Ball's Bluff, Virginia, during the American Civil War.
The Oregon Short Line Railroad came to Baker City in 1884, prompting growth; by 1900 it was the largest city between Salt Lake City and Portland and a trading center for a broad region. In 1910, Baker City residents voted to shorten the name of the city to simply Baker, the name change becoming official in 1911; Another vote in 1989 restored the name to Baker City.
The Roman Catholic Diocese of Baker was established on June 19, 1903, after which the Saint Francis de Sales Cathedral was built in Baker City. In 1918, Baker was the subject of national interest when the 1918 solar eclipse took place and the U.S. Naval Observatory based its observations there.