A federal appeals court has overturned the Federal Communications Commission’s decision to allow AT&T Inc., Verizon Communications Inc., and other wireless carriers to bypass historic preservation and environmental reviews for 5G network equipment.

The U.S. Court of Appeals for the District of Columbia Circuit Aug. 9 vacated part of an FCC order that let carriers deploy small-cell equipment on nontribal lands without any reviews. Small cells, which generally consist of radio units and antennae, can be mounted to utility poles, lamp posts, or their own towers.

The decision is a victory for American Indian tribes and environmental groups that argue...