News of his death was announced in his local paper, the Ilkley Gazette, on Thursday.
An obituary read: “CUNLIFFE John Left his Ilkley home in a deluge of rain on Thursday, September 20, never to return.
“Even the skies wept for John the gifted creator of ‘Postman Pat’, ‘Rosie And Jim’ and author of many earlier published collections of poetry and picture story books for children.
“John’s last poetry collection, significantly entitled ‘Dare You Go’ has now come to fruition for John has dared to go and he has gone.”
John’s works have entertained millions of children across a number of decades.
‘Postman Pat’ debuted on the BBC in 1981 and told the adventures of Postman Pat Clifton and his black and white cat Jess in the village of Greendale.
Nearly 200 episodes were produced until it stopped airing last year.
A spin-off film was also released in 2014, with ‘Episodes’ actor Stephen Mangan as the voice of Pat.
John also starred as the barge owner in ‘Rosie And Jim’, which featured two ragdolls who travelled on the boat and came to life to cause mischief behind his back.
It aired on ITV from 1990 to 2000, spawning 175 episodes, 50 of which John wrote and starred in.