Michael Tegza

Michael Tegza is a professional drummer. He played with several bands throughout his career, including the psychedelic group H.P. Lovecraft from is formation in 1967 through its disbanding in 1969. He joined the subsequent spin-off group "Lovecraft" in 1971, and then later was instrumental in forming two versions of the band "Love Craft" in the late 1970s and early 1980s.

Tegza's most recent activities are unknown, although he does still appear to have been alive as of 2011.

Michael Tegza in "The Fillmore Shoggoth"
Mike was the drummer of the HPL. He and the rest of the band were witness to a shoggoth attack on the Fillmore in San Francisco. He survived the attack with the rest of the band.

Literary comment
While Turtledove never explicitly gives "Mike" a last name, he provides enough clues in the story to confirm that Mike is indeed meant to be the historical Michael Tegza.