I can’t keep track of them all:
This weekend (April 6), Yale is hosting “Historiographical Heresy” to honor the legacy of American religious historian Jon Butler.
Also on April 19-20, New York University is hosting a conference in celebration of Karen Ordahl Kupperman.
On April 26-27, Princeton’s Religion Department is hosting a conference in honor of Albert Raboteau.
I also hear that there is an upcoming conference to honor T.H. Breen of Northwestern, though I am not sure if it is open to the public and can’t find anything about it on the web.