Paul Grogan was a young aide to Mayor Kevin H. White 35 years ago when he got a surprise phone call.

The booming voice on the other end of the line belonged to Vernon Jordan, the Washington power broker who was serving as president of the National Urban League.

“He said, ‘Paul, this is Vernon Jordan, and I just want to know why your boss hasn’t committed to addressing our convention,’ ’’ said Grogan, now the president of the Boston Foundation.

White, it turns out, wasn’t even aware that the group had decided to come to town, an oversight that was quickly rectified.

For a city then going through the polarizing agony of the busing crisis, entertaining a convention of black activists and professionals seemed unlikely, almost strange.