Pope.L, an uncompromising conceptual and performance artist who explored themes of race, class and what he called “have-not-ness,” and who was best known for crawling the length of Broadway in a Superman costume, died on Saturday at his home in Chicago. He was 68.

The death was confirmed by his gallery, Mitchell-Innes & Nash. No cause was given.

By 2001, when he began “The Great White Way: 22 Miles, 9 Years, 1 Street, Broadway, New York,” as the performance was ultimately titled, Pope.L was already well known in the art world for a career that comprised every medium from writing to photography, from painting to sculpture, and from performance to straight theater.

His abiding themes were the intersecting difficulties and distinctions that he experienced as a Black American and a son of the working class. But the impact of his work came less from the literal sense of its surface contents, which could be difficult to decode, than from its sheer intensity, and from his willingness to say and do things others wouldn’t. Especially when performing, he used his own bodily presence to shock viewers back into their own.

His first “crawl,” as he called them, took place in Times Square in 1978, when he moved on his belly across 42nd Street in a pinstriped suit with a yellow square sewed to the back. Getting horizontal in a relentlessly vertical city was a simple gesture that punctured most of the collective delusions that made that city run, at once lampooning and rejecting the pose of an upright citizen. It dramatized, with a potent mixture of satire and resistance, the experience of subjection particular to Black Americans. And the incongruity of a man in business attire sprawled out on the sidewalk drew attention to the homeless and disenfranchised people the average upright citizen habitually ignored.