The back-row forwards have signed deals to join Danny Wilson’s side for next season.
It takes to four the number of former Edinburgh players Glasgow have snapped up in little more than a month.
Scotland cap Simon Berghan will also make the journey west in the summer and he will be joined at Scotstoun by fellow international prop Jamie Bhatti who will arrive via Bath, the club he left Edinburgh for in December.
Miller, 24, has started six times for Edinburgh in the Guinness Pro14 this season. He is a Scotland Sevens international and can play across the back row.
The Longniddry-born flanker joined Edinburgh in 2017 from London Scottish, having come through the ranks at Melrose.
Darge, 21, captained Scotland at the 2020 U20 Six Nations, leading the team to a record 52-17 win over Wales in Colwyn Bay in the final match of the campaign.
He was one of three young players – along with Glasgow backs Jamie Dobie and Rufus McLean – who were invited to train with the squad full Scotland squad at the start of this season’s Six Nations campaign.
The openside flanker signed his first professional contract with Edinburgh last summer after playing club rugby for North Berwick and Melrose. He also played for the Southern Knights in the inaugural Super6 last season.
Wilson, the Glasgow head coach, thinks the pair can add attacking dynamism to his side.
“I’ve watched Ally play in recent games for Edinburgh,” he told glasgowwarriors.org.
“With his sevens background he’s an evasive ball carrier and has a good skill set.
“Rory is an exciting young Scottish prospect. He’s physical on both sides of the ball and a talent for the future, and it’s great to be adding more depth to an already competitive back-row.”
Edinburgh head coach Richard Cockerill explained his rationale behind the transfers.
“We’ve developed a lot of strength and depth in the back-row over a number of seasons, so this is a move that probably makes sense for both players – and Scottish rugby generally – to pursue more game time than we’ve been able to offer here at Glasgow,” he said.