Rotherham manager Steve Evans has described his side's promotion as his "most special".
Evans recorded a third successive promotion as manager, after leading Crawley to back-to-back rises, when he got the Millers back into League One after a six-year absence.
Although they were heavy pre-season favourites, they made hard work of it until a run of five wins in a row earned a second-placed finish.
"Personally it is relief," Evans said. "I have had a number of promotions but this is the most special by a country mile.
"This is a fantastic football club with an incredible fanbase, you only have to see what it means to them.
"Martin Allen said last week that he usually gets an SOS call to go and save clubs from relegation, well maybe I'll start getting them to win sides promotion."