A diplomatic breakthrough in the longstanding feud between Turkey and Armenia puts a renewed focus on the United States’ role in that dispute last year. Turkey mounted the largest foreign lobbying effort of 2008 in order to deter the U.S. Congress from declaring events in that part of the world 85 years prior as a genocide. The lobbying onslaught appeared to have worked, we’ve written on our Foreign Lobbyist Influence Tracker, but under an agreement floated this week, the Wall Street Journal reports today, the countries have taken steps to open relations while agreeing to mount a joint historical investigation into the deaths, which numbered as high as 1.5 million.

As a senator, Barack Obama supported terming the Turks’ ancestors’ actions genocide, but in an April visit to Turkey the president steered clear of the topic.

Lobbyists for Turkey made 2,268 contacts with Congressional offices in a short period, we’ve reported, more than any other country. Armenia has a presence on Capitol Hill as well, and there was pushback from that camp.

Now, direct talks between the two countries seem to be making progress, and Turkey may open its border, closed to Armenia since 1993, the Journal reports. Turkey’s worldwide image is of great concern to it as it pursues membership in the European Union.

See all contacts between lobbyists for Turkey and US officials and media, as compiled by the Sunlight Foundation and ProPublica, here and here.