On 29 April 1971 , Thompson began writing the full manuscript in a hotel room in Arcadia , California , in his spare time while completing `` Strange Rumblings in Aztlan '' , the article chronicling the death of Salazar .
On 29 April 1971 , he began writing the full manuscript in a hotel room in Arcadia , California , in his spare time while completing `` Strange Rumblings in Aztlan '' , the article chronicling the slain Chicano journalist Rubén Salazar .