From Wikipedia:
On October 14, 1964, King received the Nobel Peace Prize for combating racial inequality through nonviolence. In 1965, he and the SCLC helped to organize the Selma to Montgomery marches and the following year, he took the movement north to Chicago to work on segregated housing. In the final years of his life, King expanded his focus to include poverty and speak against the Vietnam War, alienating many of his liberal allies with a 1967 speech titled “Beyond Vietnam”.
In 1968, King was planning a national occupation of Washington, D.C., to be called the Poor People’s Campaign, when he was assassinated on April 4 in Memphis, Tennessee. His death was followed by riots in many U.S. cities. Allegations that James Earl Ray, the man convicted of killing King, had been framed or acted in concert with government agents persisted for decades after the shooting.
King was posthumously awarded the Presidential Medal of Freedom and the Congressional Gold Medal. Martin Luther King, Jr. Day was established as a holiday in numerous cities and states beginning in 1971, and as a U.S. federal holiday in 1986. Hundreds of streets in the U.S. have been renamed in his honor. In addition, a county was rededicated in his honor. A memorial statue on the National Mall was opened to the public in 2011.