GEOGRAPHY

Kentucky was once part of Virginia and became a state  June 1. 1792
Kentucky Co, VA, was formed in 1776 from the "soon to become extinct" Fincastle County. In 1780, Kentucky Co itself became extinct when it was divided into three parts forming Fayette, Jefferson, and Lincoln Counties. In 1785, Nelson Co was formed from Jefferson Co. In 1786, Madison and Mercer Counties were formed from Lincoln Co, AND Bourbon Co was formed from Fayette Co. In 1789, Mason Co was formed from Bourbon Co AND Woodford Co was formed from Fayette Co. There were political maneuverings and frequent proposals to split this region out from Virginia's control. On 18 December 1789, the General Assembly of Virginia passed an act to allow Kentucky to apply for statehood, and on 1 Jun 1792, Kentucky's nine counties became a state.
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West Virginia split from Virginia in 1861  

because the population was divided on the issue of secession from the Union during the Civil War. Many of the plantation owners in the eastern part of the state owned slaves, while plantation owners in the western portion of the state did not. Those who owned slaves dominated both the economy and politics of the state, while self-sufficient farmers had far less power.
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Washington D.C. was carved from the states of Virginia and Maryland in 1790.
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Alexandria, VA was part of Washington, DC

In 1801, the land that includes present-day Arlington County and the City of Alexandria was ceded to the federal government to become part of the new Federal District. It wasn’t until nearly a half-century later that the land was returned to Virginia sovereignty, at which point the entire jurisdiction was referred to as, “Alexandria County, Virginia.”

In 1871, the new Virginia constitution designated Alexandria City and Alexandria County as two separate and independent jurisdictions. And in 1920, by order of the Virginia General Assembly, “Alexandria County” changed its name to “Arlington County” so as to avoid any confusion with the City of Alexandria.

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