Xenia /ˈziːnjə/ ZEEN-yə is a city in and the county seat of Greene County, Ohio, United States. The municipality is located in southwestern Ohio 21 miles from Dayton and is part of the Dayton Metropolitan Statistical Area. The name comes from the Greek word Xenia (ξενία), which means "hospitality".

Many of its residents supported the Underground Railroad in the years before the Civil War.

As of the 2010 census, the city had a population of 25,719. Xenia is the third largest city in Greene County, behind Fairborn and Beavercreek.

Xenia was founded in 1803, the year Ohio was admitted into the Union. In that year, pioneer John Paul bought 2,000 acres (8.1 km²) of land from Thomas and Elizabeth Richardson of Hanover County, Virginia, for "1050 pounds current moneys of Virginia." Paul influenced county commissioners to locate the town seat on this land at the forks of the Shawnee Creeks.

Joseph C. Vance was named to survey the site and lay out the town. The following year, he bought the town site of 257 acres (1.04 km²) from John Paul for $250. The name of the new village was chosen in typically democratic fashion. Vance called a town meeting to discuss possible names. The committee had considered several suggestions without reaching any decision. Then the Rev. Robert Armstrong proposed the name "Xenia," meaning "hospitality" in Greek, because of the fine hospitality extended to him in this friendly community. When a tie developed, Laticia Davis, wife of Owen Davis, was invited to cast the deciding ballot. She voted for "Xenia."

Ohio (ⁱ/oʊˈhaɪ.oʊ/) is a state in the Midwestern United States. Ohio is the 34th most extensive, the 7th most populous, and the 10th most densely populated of the 50 United States. The state's capital and largest city is Columbus.

The name "Ohio" originated from Iroquois word ohi-yo’, meaning "great river". The state, originally partitioned from the Northwest Territory, was admitted to the Union as the 17th state (and the first under the Northwest Ordinance) on March 1, 1803. Although there are conflicting narratives regarding the origin of the nickname, Ohio is historically known as the "Buckeye State" (relating to the Ohio buckeye tree) and Ohioans are also known as "Buckeyes".

The government of Ohio is composed of the executive branch, led by the Governor; the legislative branch, which comprises the Ohio General Assembly; and the judicial branch, which is led by the Supreme Court. Currently, Ohio occupies 18 seats in the United States House of Representatives. Ohio is known for its status as both a swing state and a bellwether in national elections.