GROTON, Conn. — For the first time in 40 years, students from a Naval Reserve Officers Training Corps unit are among the freshmen at Yale University.

The appearance of midshipmen for classes beginning Wednesday is also leading to new ties with the Naval Submarine base about 50 miles up the shoreline in Groton.

Since the Ivy League school agreed last year to bring back ROTC after the repeal of ‘‘don’t ask, don’t tell,’’ military officials have welcomed Yale faculty on base tours and taken some for a ride on a nuclear submarine.

The commanding officer of the base, Captain Marc Denno, hopes to develop a tighter relationship — and perhaps inspire Yale-educated officers to pursue careers in the submarine force.

‘‘The synergy is obvious and necessary,’’ said Denno.

‘It’s important for them to understand we’re not a lot of knuckle-draggers.’

Eleven Yale undergraduates, including one sophomore, are enrolled in the Naval ROTC unit. The Air Force and the Navy are both opening ROTC detachments this fall at Yale’s New Haven campus, which welcomed them back after Congress voted to allow gays to serve openly in the military.

ROTC has not had a presence at Yale since the Vietnam War, but its return renews a long tradition. Inventor David Bushnell is credited with creating the first submarine used in combat while he studied at Yale in 1775.

Students in the ROTC program get scholarship money in return for agreeing to military service after graduation.

The Groton sub base expects to support the students in a number of ways, including hosting them for visits to use training and team-building equipment. ROTC officials also have sought to build connections with the faculty.

‘‘It’s important for them to understand we’re not a lot of knuckle-draggers,’’ said Navy Commander Jamie Godwin.

Harvard and Columbia universities agreed last year to bring back ROTC.

ROTC programs left many campuses in the late 1960s and early 1970s in the fervor of student protests against the Vietnam War. ROTC was kept away more recently because of ‘‘don’t ask, don’t tell,’’ which banned gays from serving openly in the armed services.

Vincent Wilczynski, a deputy dean at the Yale School of Engineering & Science, accompanied the crew of the submarine USS Missouri on a three-day transit from the Bahamas to Georgia.

‘‘It was tremendous,’’ he said. ‘‘It was a good reminder of the end game.”