First released by John Michael Montgomery (US #42/C&W #1 1993).
Hit version by All-4-One (US #1/R&B #13/UK #2/CAN #1/AUS #1/NETH #1 1994).
From the wiki: “‘I Swear’ was written by Gary Baker and Frank J. Myers, who also recorded a demo of it in 1989 at Fame Studios in Muscle Shoals, Alabama. They couldn’t convince anyone to record the song at the time but, in 1992, they recorded a new demo of ‘I Swear’ which attracted the attention of John Michael Montgomery. Montgomery would record the song in 1993 and release it as the first single from his 1994 album Kickin It Up.
“Atlantic Records thought the song had huge crossover potential, and considered having Montgomery record a Pop version. The label head didn’t want to upset Country radio stations, so the label had their new vocal group All-4-One record the song with David Foster producing the track. The All-4-One version was released as the second single from the group’s debut album in the spring of 1994, about 6 months after Montgomery’s rendition was released as a single. All-4-One’s recording won a Grammy in 1995 for Best Pop Performance By A Duo Or Group With Vocal, and was also ranked at #78 on Billboard’s Top 100 songs in the 50-year history of the Billboard Hot 100 chart.”
All-4-One, “I Swear” (1994):
Gary Baker talks about co-writing ‘I Swear’: