Probably the most racist thing I've ever seen in an official fraternity publication..

[naraht]

Originally Posted by Kevin

Since we voted to accept minorities back in 1969, a lot of our chapters have become pretty diverse. Our Dartmouth chapter actually left Sigma Nu entirely until we integrated. There was a pretty legendary fight over integration at our 1969 Grand Chapter. Future Senator Trent Lott led the fight against integration and was successful the first time it was proposed.

According to the Wikipedia article on the Dartmouth GLOs.
The Dartmouth chapters of Alpha Chi Rho, Chi Phi, Delta Upsilon, Phi Gamma Delta, Phi Kappa Psi, and Sigma Phi Epsilon all disaffiliated from their national fraternities in the 1960s.

Later in the article specifically for Sigma Nu it says
In response to the national fraternity's segregationist membership policies, the fraternity went local in 1963, becoming Sigma Nu Delta. In 1984, after the national fraternity's policies were changed, the fraternity reaffiliated with the national.