League sources told ESPN and NFL Media that Kansas City sent its first-round pick (No. 31 overall) in next week's NFL Draft to the Ravens in exchange for Brown, a 2021 second-round choice (No. 58) and a 2022 sixth-rounder.
The Ravens also acquired a 2021 third-rounder (No. 94) and fourth-rounder (No. 136) as part of the deal, as well as a fifth-round selection in 2022.
The teams confirmed the blockbuster trade, pending a physical, but they didn't disclose terms of the agreement.
The Ravens had been open to moving Brown since his Jan. 29 tweet in which he wrote: "I'm a LEFT tackle."
The 24-year-old Brown, who filled in for injured left tackle Ronnie Stanley for the last 11 games this past season, indicated that his late father wanted him to play left tackle, and he wished to fulfill his father's dream.
After dealing Brown, the Ravens are expected to replace him at right tackle with former Pittsburgh Steelers offensive lineman and current free agent Alejandro Villanueva, according to ESPN. Villanueva visited the Ravens on Thursday.
Brown started 42 games for the Ravens since the franchise selected him in the third round of the 2018 draft out of the University of Oklahoma. According to Pro Football Focus, he allowed no sacks or quarterback hits in 389 pass-blocking snaps at left tackle last season.
Brown was one of four offensive tackles named to the Pro Bowl in each of the last two seasons, along with David Bakhtiari, Laremy Tunsil and Terron Armstead.