ANCHORAGE — Gay couples began applying for marriage licenses in Anchorage on Monday, 15 years after Alaska helped touch off a national debate with a ban on same-sex unions.

“It feels very surreal,” Ann Marie Garber said.

Garber and her partner, Koy Field, were among the first gay couples seeking a license to wed in Alaska. “I had no idea this would happen in my lifetime,” she said.

They decided to apply immediately after the ban was overturned by a federal judge Sunday.

“This is historical,” Garber said. “It’s exciting.”

U.S. District Court Judge Timothy Burgess ruled that the gay marriage ban violated the due process and equal protection guarantees of the U.S. Constitution. His ruling came over the objection of gay marriage opponents who say states should decide the issue, not courts.

The ruling in favor of five couples who sued the state in May overturns a constitutional amendment approved by Alaska voters in 1998, defining marriage in the state as between one man and one woman.

It bars enforcement of any state law that keeps gay couples from marrying or refuses to recognize same-sex unions performed elsewhere.

Gay couples married outside of Alaska or in ceremonies within the state that didn’t carry legal standing were among those seeking licenses. There is a three-day waiting period in Alaska, so the first ceremonies couldn’t take place until Thursday.

Christopher Ruff and Peter VanDyne plan to renew their vows as soon as they are allowed to do so Thursday.

“We want to make sure we get in the window in case they close the window and say you can’t get married anymore,” VanDyne said.

The Alaska attorney general’s office planned to take its case to the 9th Circuit Court of Appeals within the coming weeks and filed notice Monday.

The landscape has changed very quickly for gay marriage in the U.S. Last week, the U.S. Supreme Court declined to hear appeals from several states seeking to retain their bans on same-sex marriage. The Oct. 6 move effectively legalized gay marriage in about 30 states and triggered a flurry of rulings and confusion in lower courts across the nation, including the Alaska decision.

The lead plaintiff in the Alaska lawsuit was Matthew Hamby, who helped other couples through the application process Monday before completing his own.

He and his husband, Christopher Shelden, plan to renew vows they made in their 2008 marriage in Banff, Alberta, Canada. They haven’t set a date yet, but the $60 licenses are good for three months.

“We’ll take our time,” Hamby said.

Garber and Field filled out their application, which the state Department of Vital Statistics reworked overnight to replace “bride” and “groom” with “Party A” and “Party B.” They’re already planning their December wedding.

“We just knew we were meant to be together,” Field said. “And now it’s just on paper.”