Residents were shocked after the plaque was taken from Ethelfleda Memorial Gardens in Church Hill, Wednesbury last year.
Police were able to recover it from the West Bromwich scrapyard after a tip-off someone was trying to sell it on. Now, fearing metal thieves could strike again, the council has installed a new granite plaque on the memorial stone, and is planning to keep the original in Wednesbury Museum.
"We just thought 'if we put a granite plaque in, no-one is going to steal it'," said Wednesbury town councillor Elaine Costigan. "The last plaque was there for years and years and when it was taken everyone was devastated. I was inundated with calls and I think one of the reasons the police recovered it so quickly is because they were being bombarded by members of the public.
"We don't want to have to go through that again."
Sandwell Council has spent £700 creating the new plaque and restoring the old one.
The 3ft by 2ft commemoration was presented to Wednesbury hundreds of years ago by Queen Ethelfleda, the eldest daughter of Alfred the Great, king of the Anglo-Saxon kingdom of Wessex.
Wednesbury was one of five fortifications used to defend against Danish invaders during the Anglo Saxon period.
Rev Tim Vasby-Burnie, vicar of nearby St Bartholomew's church and relative of Queen Ethelfleda, said he understood she fortified the hill top where the church now stands. Welcoming the return of the plaque, he said: "It's good to have the connection highlighted again. It's a real link to the past. It's particularly of interest to me because they were part of my family tree.
I understand Alfred the Great was something like my 26-time great grandfather so there's always been a personal interest."
Officers visited scrap dealerships in the area after the plaque was stolen last year. Two men, aged 24 and 30, of Friar Park, Wednesbury, were arrested at a scrapyard in West Bromwich.
The younger man was sentenced to 20 weeks in prison, and the 30-year-old was handed a suspended 20-week sentence and a 12-month supervision order.