One reason there is no East Virginia is that the government of Virginia during the Civil War did not really accept West Virginia as a legitimate state. read more
West Virginia came long after Virginia. It's like why we don't call York Old York after New York came around. read more
On June 20, 1863, West Virginia joined the Union, leaving Virginia as a confederate state. There is no East Virginia because it has always been called just "Virginia." It's likely that there will never be an East Virginia unless the Eastern portion of Virginia becomes its own state. Then there would be a West Virginia, Virginia, and East Virginia. read more