A longtime D.C. jazz bassist with a prodigious career but troubled life, Butch Warren died of lung cancer on Oct. 5 at the age of 74. He was the house bassist for Blue Note Records in the early 1960s, then played for two years with the Thelonious Monk Quartet before returning to D.C. to recover from drug addiction and mental illness. His presence in D.C. jazz was intermittent (he was in and out of hospitals and psychological institutions), but seminal, including long stretches at Twins Lounge and Columbia Station. It was also keenly felt by local musicians as well as those passing through. In a music that values its ancestors with intensity, Warren was regarded as a civic treasure: He was a link to the scene’s golden age, a torch carrier for the D.C. bass sound, and a survivor of the music’s darkest impulses. He was also a teacher and mentor, albeit on idiosyncratic (and erratic) terms. His death, though not entirely unexpected, was a tremendous blow to the legacy of jazz in the District.