WASHINGTON — The cat has landed.

After keeping the nation on tenterhooks since even before taking office, the Biden White House announced on Friday that a gray cat named Willow had joined the first family, more than a year after the plucky farm feline from Pennsylvania caught the eye of the first lady, Jill Biden, while she was on the stump for her husband.

“Willow made quite an impression on Dr. Biden in 2020 when she jumped up on the stage and interrupted her remarks during a campaign stop,” said Michael LaRosa, the first lady’s spokesman. “Seeing their immediate bond, the owner of the farm knew that Willow belonged with Dr. Biden.”

Willow is named after the first lady’s hometown, Willow Grove, Pa.

The cat’s arrival was much anticipated after Dr. Biden casually mentioned in a November 2020 interview that she’d love to have a cat in the White House, and later lightheartedly suggested that the animal was “waiting in the wings.” To feline fans everywhere, this might as well have been a blood oath that a cat would soon be revealed.

For more than a year, Jen Psaki, the White House press secretary, was peppered with questions about the administration’s cat policy by reporters and other interested parties. She seemed aware of the stakes behind the cat’s public rollout.

“I’m also wondering about the cat,” she said during a question-and-answer session with Twitter users last January, “because the cat is going to dominate the internet.”

On Wednesday, Willow, a shorthair tabby with jade-green eyes, formally moved into the White House, just over a month after the Bidens revealed that they had added Commander, a German shepherd puppy, to the mix. Dr. Biden said in an interview with The New York Times this fall that the cat had been living with a foster parent who had grown attached.

“The cat is still being fostered with somebody who loves the cat,” Dr. Biden said. “I don’t even know whether I can get the cat back at this point.”

Another complication, Dr. Biden said at the time, was concerns of hostility between the cat and Major, the family’s other German shepherd, who had been sent to training after a series of biting episodes in the East Wing. At the time, Mr. LaRosa described it as “some additional training to help him adjust to life in the White House.” But last month, Major was sent to live in a quieter environment with friends of the family, Mr. LaRosa said.

A set of photos released by the White House show Willow adapting to her new surroundings, sprawling on a coach and taking in a view of the Washington Monument.

“Willow is settling into the White House with her favorite toys, treats and plenty of room to smell and explore,” Mr. LaRosa said.

The last feline to live in the White House was India, a black cat who belonged to President George W. Bush and his wife, Laura. Then there was Socks, the black-and-white resident feline of the Clinton White House. Socks, a bit of a media darling, was the protagonist of an unreleased Super Nintendo game, “Socks the Cat Rocks the Hill,” and was even photographed in the White House briefing room.

Presidential cats go back to at least the Lincoln era, when Abraham Lincoln’s secretary of state, William H. Seward, gave him two cats, Tabby and Dixie. Lincoln, historians have said, once remarked that Dixie was smarter than his entire cabinet.