He learned to box in rough schoolboy bouts, but trained for the profession in earnest by 13 when he began taking lessons at McGurn's Handball Courts in Chicago.

[3] Showing his championship form, on February 6, 1894, the blond Chicagoan faced future Irish bantamweight champion Joe McGrath at Chicago's Empire Theatre, knocking him down in less than a minute into the first round.

[6][7] Several boxing historians consider Barry's first ascent to the USA Bantamweight World championship for the 102-pound (46 kg) class to have come after his defeat of Jimmy Gorman on June 2, 1894, at the Olympic Club New Orleans, Louisiana.

Barry's best-known fight became his 28th-round knockout of Sicilian boxer Casper Leon before a seasoned crowd of 250 on September 15, 1894, in Lemont, Illinois, for total stakes of $4,000.

[2][3][9][10][11] Barry faced Casper Leon a second time on March 30, 1895, for both the USA and World 105 lb championship, and retained the title with a 14-round draw.

[12] Barry defeated Jimmy Anthony, a onetime holder of the Australian welterweight championship, on April 23, 1897, winning a 20-round bout in San Francisco.

In the 19th, Barry landed strong counters to the jaw of Anthony, who had received a series of punishing blows to his eyes in several rounds of the fight.

[13][14] On December 6, 1897, Barry scored a 20th-round knockout with a crushing right to the jaw against English champion Walter Croot in London, giving him claim to the vacant 110-pound (50 kg) World championship.

Charged with manslaughter, Barry was exonerated when it was determined that Croot had died from a fractured skull sustained when his head hit the unpadded floor, made of wood.

The Scranton's Tribune wrote that Flanagan may have had the better of the bout, clearly dominating the third, and landing the last solid blow in the sixth on Barry's eye.

[22][23] Barry faced Casper Leon again for the American and World 110-pound (50 kg) bantamweight championship in the late evening of December 29, 1898, and retained the title in a 20-round draw.

Chicago's Inter-Ocean wrote that Harris "clearly outpointed Barry and during the last few rounds forced the fighting after a fashion that should have gained him the decision".

The Chicago Tribune wrote that Barry was fortunate to receive a draw as Harris showed considerable skill in avoiding his blows.

World War I Army boxing training was led by several exceptional featherweight and lightweight champions including Benny Leonard, Packey McFarland and Johnny Kilbane.

[30] After his war service, Barry worked in Chicago's Cook County clerk's office for 25 years until he left due to poor health.

[32][33] According to the International Boxing Hall of Fame, which inducted the diminutive pugilist in the Old Timer category in 2000, Barry was undefeated in 70 professional fights.