The Yesterdays column in the Hungry Horse News mentioned several bear incidents including in 1983 what is reputed to be the first use of bear spray in the Park.
When I worked in the Park 1970 - 72 and when I went back for visits in 1975 and 1977 I never heard of bear spray and it probably hadn't been invented then.
"Oct. 7, 1983
In two separate incidents, hikers in Glacier National Park used pepper spray to deter charging grizzly bears. The incidents were believed to be the first time the spray was used to stop a bear in the park. Tim Rubbert’s encounter was a dramatic one. He sprayed a grizzly while the bear attacked his friend, Jim Cole. The bear went after Rubbert and he sprayed it. Once the spray hit the bear, it veered off. Cole suffered a broken bone in his wrist and a head wound to his scalp where the bear bit him. It was put back together with a surgical staple.
20 years ago
Oct. 2, 2003
Kathryn Heistand of St. Mary probably saved her friend Kelsey Ray Running Wolf’s life when she sprayed a bear with bear spray that jumped on Running Wolf during a hike in Many Glacier near Mount Allen. The bear first pinned Heistand against a tree and then jumped on Running Wolf. The two women weren’t seriously injured, but they did get covered with the spray, which is highly unpleasant."