Williams was born in Nassau, The Bahamas, on November 12, 1874, to Frederick Williams Jr. and his wife Julia. At the age of 11, Bert permanently emigrated with his parents, moving to Florida. The family later moved to Riverside, California, where he graduated from Riverside High School. In 1893, while still a teenager, he joined different West Coast minstrel shows, including Martin and Selig's Mastodon Minstrels, where he first met his future professional partner, George Walker.

The following month, Williams & Walker had their greatest success to date with Sons of Ham, a broad farce that was perhaps most notable for its lack of the extreme "darkie" stereotypes which were then common. One of the show's songs, "Miss Hannah from Savannah," even touched upon class divisions within the black community. The pair had already begun to transition away from racial minstrel conventions to a more human style of comedy. In 1901, they recorded 13 discs for the Victor Talking Machine Company. Some of these, such as "The Phrenologist Coon," were standard blackface material, but the financial lament "When It's All Going Out and Nothing Coming In" was race-blind, and became one of Williams' best-known songs. Another Williams composition, "Good Morning Carrie", was covered by many artists, becoming one of the biggest hits of 1901. These discs existed only in pressings of fewer than 1,000, and were not heard by very many listeners. Sons of Ham ran for two years.  In September 1902, Williams & Walker debuted their next vehicle, In Dahomey, which was an even bigger hit. In 1903 the production, with music by Will Marion Cook and lyrics by Paul Laurence Dunbar moved to New York City, where it became the first black musical to open on Broadway. Part of the inspiration for the show was Williams' copy of a 1670 book, Africa, in which author John Ogilby traced the history of the continent's tribes and peoples. "With this volume, I could prove that every Pullman porter is the descendant of a king," said Williams.  This was a landmark event, but seating inside the theater was segregated. One of the musical's songs, "I'm a Jonah Man," helped codify Williams' hard-luck persona and tales of woe. It helped to establish the character Williams played most frequently in his career: the slow-talking, deep-thinking victim of life's misfortunes. "Even if it rained soup," Williams later explained, "[my character] would be found with a fork in his hand and no spoon in sight." However, Williams and Walker were ebullient about their Broadway breakthrough, which came years after they had established themselves as profitable stage stars. Williams wrote, "We'd get near enough to hear the Broadway audiences applaud sometimes, but it was some one else they were applauding. I used to be tempted to beg for a $15 job in a chorus just for one week so as to be able to say I'd been on Broadway once." Walker recalled, "Some years ago we were doing a dance before an east side audience. They gave us a hand, and I called out to them, "Some day we'll do this dance on Broadway!" Then they gave us the laugh. Just the same we gave Broadway that same dance."  In Dahomey then traveled to London, where it was enthusiastically received. A command performance was given at Buckingham Palace in June 1903. The show's British tour continued through June 1904. In May, Williams and Walker were both initiated into the Edinburgh Lodge of the Freemasons; the Scottish Masons did not racially discriminate as the United States chapters did, including the northern states.

How long did it run for?
tour continued through June 1904.