Calder in Waterbury

Although the legendary sculptor Alexander Calder has been mentioned frequently in connection to the new artworks in downtown Waterbury, I haven't seen anyone delving into the history of Calder's Waterbury connections, so I figure I might as well do it here.

Alexander Calder at "Stegosaurus" dedication, Hartford, October 10, 1973
Collection of Hartford History Center, Hartford Public Library
and Connecticut History Illustrated

If you don't have a background in art or art history, you might be wondering, why Calder? Why is he so famous? Why would five artists come all the way from Italy (twice) for the opportunity to create art in the same city in which many of his sculptures were made?