It is an unusual system. In my day, fraternity, sorority, independent living group, and dorm rush all happened concurrently, starting the day after most freshmen arrived on campus. Can you say stress?!?!?!
The way it worked was:
- You were assigned to a temporary room somewhere in the dorm system.
- All freshmen attended a convocation, where at a designated time, the IFC president would shout "LET THE RUSH BEGIN!" and upperclassmen in Greek lettters would descend upon the freshmen and whisk them off to rush activities.
- Dorms held a variety of rush activities, including building tours, barbecues, a "gravity demonstration" at the only undergrad dorm with a tower, etc. Freshmen could come and go as they pleased.
- Fraternities and independent living groups (which were mainly coed fraternities) held their rush. Men interested in fraternity/ILG membership and women interested in ILG membership didn't necessarily have to visit the dorms, because the minute you signed, you moved into the house.
- NPC sororities also held formal fall recruitment. Women interested in NPC sorority membership also had to go through dorm rush, as only one sorority had a house.
- To muddy the waters further

people interested in living in the language houses or Chocolate City would rush those groups at the same time. The language houses and Chocolate City were all located in the same dorm, and as with GLOs, you had to be invited to join.
- If you went through dorm rush, you would enter a lottery, ranking the dorms in preference order, and then get your dorm assignment. The dorms got no input other than "we have x number of beds, at least y of which must go to women, and z of which must go to men, and the rest can be either gender". (There were single-sex suites, half-open doubles, etc. hence some beds had to be assigned to one gender or the other.)
- In certain dorms, including mine, you would get another temp room in that dorm, then go through floor/entry/hall rush. In my dorm, each floor had its own distinct personality, so floor rush was important.
All of this took place over the course of less than a week. There was a mentality that "you're picking your friends for the next four years" and every year a few freshmen just cracked under the pressure.
Things are going to be spread out a bit more now. Fraternity rush was moved to September, and sorority rush is going to take place over Labor Day weekend rather than late August. This means academic orientation will happen first, and the freshmen will have a chance to get their bearings and maybe make a few friends before plunging into rush.