Louis turned up at Wells Cathedral in Somerset over 16-years ago. Back then, he was just a raggedy ginger stray with no home or family.
Everyone fell in love with Louis
But then cathedral staff fell in love with the furry little guy and decided to adopt him. Louis soon became a popular site around the Cathedral, charming the staff and visitors with his antics.
He even featured in a BBC documentary, where a cat-cam was fixed to his collar to show us what he got up to when his human friends weren't around.
He was the also the subject of a book, Louis the Cathedral Cat, written by local author and illustrator Babara Cooke.
After cathedral staff released the sad news via Twitter, messages of condolence came in from all over the world.
Such sad news. Louis is now chasing mice in heaven.— English Cathedrals (@engcathedrals) November 17, 2019
Louis the Wells Cathedral Cat has passed away.
RIP Louis, you'll be missed. pic.twitter.com/OTORVbgNdF
Jackie Croft, a Cathedral spokesperson, also released a statement. She wrote:
"It is with heavy hearts we say goodbye and goodnight to the gentlemanly, charismatic, adorable ginger boy."
Louis wasn't the first church cat. In fact, many churches and monasteries once kept a resident kitty to help control local pests, including rats and even snakes.
More pets in church
And while there'll always be a place for working cats, more and more churches are introducing pet-friendly services.
But there's one furball who didn't need an invitation. 'Junior' the stray showed up at a parish church in Brazil a few months ago and simply refused to leave.
The handsome fella would plonk himself down on a lucky person's lap during prayer time or curl up on the altar next to the priest during service.
Thankfully, worshippers appreciated Junior 'donating' himself to the church, and he's now a permanent resident.
Let's hope he has a long and happy life - just like Louis did!