The Klamath Indians were the first inhabitants of the area. Their name for this place was Yulalona or Iwauna, which referred to the phenomenon of the Link River flowing upstream when the south wind blew hard. Their name for the falls was Tiwishkeni, or "where the falling waters rush".
The Modoc Tribe's homeland is about 20 miles south of Klamath Falls, and the war of 1872 - 1873 was a hugely expensive campaign for the US Cavalry, costing an estimated $500,000--the equivalent over 8 Million in yr 2000 dollars. 17 Indians and 83 whites were killed. 
The Applegate Trail, which passes through the lower Klamath area, was blazed in 1846 from west to east in an attempt to provide a safer route for emigrants on the Oregon Trail.
The Klamath Reclamation Project began in 1906 to drain marshland to allow for agriculture. With the building of the main "A" Canal, water was first made available May 22, 1907. Veterans of World War I and World War II were given homesteading opportunities on the reclaimed land. 
During World War II, a Japanese-American internment camp, the Tule Lake War Relocation Center, was located in nearby Newell, California, and a satellite of the Camp White, Oregon, POW camp was located just on the Oregon-California border near the town of Tulelake, California. In May 1945, about 30 miles east of Klamath Falls, (near Bly, Oregon) a Japanese balloon bomb killed a woman and five children on a church outing. This is said to be the only Japanese-inflicted casualty on the US mainland during the war.
Timber harvesting through the use of railroad was extensive in Klamath County for the first few decades of the 20th century.
With the arrival of the Union Pacific in 1909, Klamath Falls grew quickly from a few hundred to several thousand. Dozens of lumber mills cut fir and pine lumber, and the industry flourished until the late 1980s when the Northern Spotted Owl and other endangered species were driving forces in changing western forest policy.
This may have led to mass die-off of the salmon, practically shutting down the fishing industry in the region and leading to over $60 million in disaster aid being given to fishermen to offset losses.
In March 2006, the plan was found to be in violation of the Endangered Species Act and a new ruling was made to shut off irrigation if natural water levels go below a specified point.
According to a National Academy of Sciences report of October 22, 2003, limiting irrigation water did little if any to help endangered fish and may have hurt the populations. However, this report has been widely criticized as politically motivated.
According to the United States Census Bureau, the city has a total area of 18.7 sq mi (48.5 km²). 17.9 sq mi (46.3 km²) of it is land and 0.9 sq mi (2.2 km²) of it (4.54%) is water.
Klamath Falls has a high desert landscape. The older part of the city sits on natural geothermal springs. These have been used for the heating of homes and streets, primarily in the downtown area.
The racial makeup of the city was:
9.32% of the population are Hispanic or Latino of any race.
There were 7,916 households out of which:
The average household size was 2.36 and the average family size was 2.99.
The age distribution was:
The median age was 33 years. For every 100 females there were 101.9 males. For every 100 females age 18 and over, there were 100.1 males.
The median income for a household in the city was $28,498, and the median income for a family was $37,021. Males had a median income of $31,567 versus $22,313 for females. The per capita income for the city was $16,710. About 21.9% of the population and 16.2% of families were below the poverty line, including 26.8% of those under age 18 and 9.5% of those 65 or over.
Klamath Falls is home to the 173rd Fighter Wing of the Oregon Air National Guard, stationed at Kingsley Field airbase.
and the Klamath Falls City School District
These two districts combined provide schools for the residents of Klamath Falls and its out lying areas.
and Henley Middle School 
, Peterson
, Shasta
, and Stearns 
and Mazama 

, Fairview
, Mills
, Pelican
, Roosevelt 
Klamath Falls is located on the Pacific Flyway, and large numbers of waterfowl and raptors are seen at all times of the year. The largest concentration of Bald Eagles in the lower 48 winter in Bear Valley, just 10 miles west of Klamath Falls, near Keno, and the American White Pelican shows in great numbers in summer.
Crater Lake National Park is 50 miles north of Klamath Falls and the 33 mile rim drive circling the lake is a favorite of cyclists. Winter cross country skiing in the park is also very popular. The more than mile high Crater Lake Marathon
is an annual event.

, as designated by Sister Cities International: