In 2036 when the Purge had first started Washington D.C. was put on lock down, and martial law. In early 2037 Captain America the 1st, and General Bryan commanded the CPAA to kill anyone who they took as a threat. The death toll easily hit 20,000 in less than a year. Many of the first deaths were the politicians in Washington D.C at the time. General Bryan pressured that the capital had to be cleansed first before the country. The cleansing in D.C was the base for the rest of the Great Purge. Many important documents in the museums were burned, or locked away in CA1's personal vault.
The resistance mainly came from the the dis-banned U.S Army, and the remaining politicians that survived the first two years of the purge. As the battle led on the U.S Army eventually surrendered to Bryan's forces. Many were sent away to Cuba to work as slaves or were killed for fighting.
There were still small pockets of militia groups in surrounding suburbs. They did minimal damage, and were not taken care of.
Transforming the Capital
In early 2038 Captain America the 1st started his transformation of the to be capital city to a Communist industrial oasis. The transformation took a very long time lasting over 5 years. He started by tearing down all monuments to freedom, and replacing them with monuments to Communism.
Then he quickly closed all businesses still open during the Purge, and replaced them with American Productions, a mass economic Empire, but unlike others was run by the government of the UAE, and headed by the Emperor. He continued by getting rid of all political influences in, and near D.C., and replaced it with the UAE Communist agenda.
Nobody could stop what America had set upon D.C. The CPAA kept killing many until CA commanded the order of all killing to cease in mid 2044. The effects kept on in the devastated capital until early 2050. The overall death toll was about 780,000 people. 50,000 military men gave their lives from both sides. D.C has since then been rebuilt.
CA1 decided to let Washington D.C. keep it's name to remind the country that he was able to win the Purge against all odds.