The upstart series will open in Kingston, Jamaica, on April 4-6 before a second meet in Miami on May 2-4. It will then move to Philadelphia on May 30-June 1 before ending at UCLA's Drake Stadium in Los Angeles where the overall series champions will be crowned.
"We're eager to bring the event to this iconic city and can't wait to give fans an unforgettable experience. It's a new era for the sport, and we're delighted to be leading the way," Johnson said in a statement.
The Guardian newspaper reported this week that UK Athletics turned down the chance to host one of the four meets in either London or Birmingham because of the British federation's difficult financial situation.
The series offers total prize money of $12.6 million and will include 48 athletes, headed by two-time Olympic 400m hurdles champion Sydney McLaughlin-Levrone, who will compete in all four meets.
They will receive a base fee and the chance to earn more with licensing and other revenue opportunities.
Another 48 racers will be paid to compete in individual meets for appearance fees.
Grand Slam says the aim of the series is "a focus on fierce rivalries and thrilling competitive racing".
The series, which will compete with the established Diamond League circuit, has caused some disquiet in the world of athletics because it does not include any field events.