Routis made his professional debut in February 1919 aged eighteen, when he beat Yves Gram by a four-round points decision.

He fought three times in April of the same year; a victory over Georges Gloria was followed by a draw with Bobby Diamond and his first loss, a ten-round decision against Emile Juliard in Paris.

Over the next fourteen months Routis fought eleven times in Morocco, losing twice, including an unsuccessful challenge for Charles Ledoux's EBU bantamweight title.

The two boxers fought a rematch in May 1923, for the EBU and French title, with the result the same as the first fight, a fifteen-round decision win for Ledoux.

After his return to France Routis fought another future world champion, Panama Al Brown, this time winning over ten rounds.

After a draw against Johnny Cuthbert in Paris, he returned to the United States and won five fights in a row, which led to his first attempt at a world title.

After winning the first two rounds Brown was knocked down three times in the 3rd, causing the corner to throw in the towel, giving Routis a technical knockout victory.

[1] A veteran of the French Colonial Army, Routis spent two years based in Morocco as a mechanic in the air corps.