Chad Allan, the founding singer and guitarist for the Guess Who, is being treated at a British Columbia hospital after suffering a stroke. His publicist told CBC News that the stroke was "pretty serious, but he is responding."

Before their string of chart-topping hits in the late '60s and early '70s, the Guess Who had undergone several name and lineup changes. Allan formed the band in 1965, after leading other groups since the late '50s. They soon scored a regional hit with "Shakin' All Over," which was originally credited to Chad Allan & the Expressions. Even though he was the Guess Who's leader at the time, Allan exited in 1966, four years before the band's commercial breakthrough.

They eventually settled on the lineup that would record the group's signature song, "American Woman." The same-titled 1970 album reached No. 9 in the U.S. and sent three consecutive singles into the Top 5: "No Time," the No. 1 "American Woman" and "No Sugar Tonight," "American Woman"'s B-side.

Allan collaborated with fellow ex-Guess Who bandmate Randy Bachman in 1971, when the two formed the short-lived country-rock group Brave Belt. Over the next year they evolved into their second and most commercial incarnation, under the name Bachman–Turner Overdrive, but Allan had left the band shortly after the release of Brave Belt's second album.

The Guess Who officially disbanded in 1975. The band reformed with a number of different past members from the late '70s until today, but Allan has been absent from all of the lineups. He continued to produce solo albums until 1992, before vocal cord damage had prevented him from singing professionally. Since then, he had taken up painting and performing instrumental music for senior citizens in Vancouver, where he's lived since 1977.

In 2015, Allan received the Order of Manitoba "for his contributions to the Canadian music industry including the pivotal role he played in the creation of two legendary Winnipeg rock bands: the Guess Who and Bachman-Turner Overdrive."

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