Live At Leeds (1970) is The Who's first live album, and indeed is their only live album that was released while the band was still recording and performing regularly.
The Who didn't play live before 1970.
Their first live album was recorded in 1970 but the article doesn't mention whether or not they had played live before that. They probably did but based on the information given we don't know. I think the system had difficulty because I used words and the date from the article. 
( z1 play :polarity - :ARG0 ( z2 band :name ( z3 name :op "The" :op "Who" ) ) :time ( z4 before :op ( z5 date-entity :year 1970 ) ) :manner ( z6 live ) )