Jan Pieńkowski, the beloved illustrator and author of more than 140 children’s books, has died aged 85.

Pieńkowski, whose work included the Meg and Mog pop-up books, had been living with Alzheimer’s.

Francesca Dow, the managing director of Penguin Random House Children’s Books, confirmed that he died on Saturday morning.

Pieńkowski’s work was often inspired by his Polish childhood and experiences as a wartime refugee. His interest in paper cut-outs stemmed from his time in an air raid shelter in Warsaw, where a soldier had kept him amused by cutting newspapers into shapes for him.

Meg and Mog, completed in collaboration with the late writer Helen Nicoll, was a series of illustrated adventures about a hapless witch and her stripy cat.

Pieńkowski said in an interview that the series gave him the opportunity to turn monsters from his childhood into harmless toys. He took his palette from comic strips such as Desperate Dan and Dennis the Menace.

“Jan was one of the great storytellers: an exceptionally talented creator, who was led by what interested him, and who treated children as his equals,” Dow said on Sunday.

“There was an impatience and wonderful curiosity to him, as he looked for new ways to tell stories: drawing on his Polish roots with his cut-out and silhouette work; his extraordinary use of colour; his pioneering interest in drawing on the computer; and of course his award-winning pop-ups which challenged publishers and printers to find new ways to create his books.”

Pieńkowski, she added, pored over every detail meticulously “and yet achieved the near-impossible: simple, magical storytelling, which is why his books – such as my personal and our family favourites, the brilliant Meg and Mog stories – endure. I was very lucky to have had the chance to know him and to work with him.”

After Nicoll died in 2012, Pieńkowski worked on new Meg and Mog titles with his civil partner, David Walser, a translator, artist, musician and writer.

“One thing I’ve noticed over the years is that Jan never treats children as children,” Walser said a few years ago. “It wouldn’t occur to him to talk down to them, he just behaves perfectly normally … When he works with children, he’s one of them.”

The British author Ed Vere, who is godson to Walser, said: “Jan Pieńkowski lived an inspiring life dedicated to making books of the very highest standard – pioneering, intelligent, beautifully considered, and always created with a mischievous sense of fun.”

He added: “Full of love, curiosity, art, thought, enjoyment and laughter. He will be much missed, as a man, and as a towering figure in children’s books.”

For his work as a children’s author, Pieńkowski was awarded the 2019 Booktrust lifetime achievement award, which has in the past gone to some of the greatest names in children’s books, including Shirley Hughes, Raymond Briggs and Judith Kerr.

The critic Nicolette Jones, who chaired the judges selecting Pieńkowski for the award, said he “brought magic to children’s illustration”, while her fellow judge, the author SF Said, said: “Books such as Meg and Mog have shaped so many generations now that they have become part of the fabric of British childhood and culture in general.”

Pieńkowski was also twice the UK nominee – in 1982 and 2008 – for the international Hans Christian Andersen award, the highest recognition available to creators of children’s books.

He won the Kate Greenaway award in 1971 with the writer Joan Aiken for their second collaboration, The Kingdom Under the Sea, which was comprised of eastern European fairytales. He won his second Greenaway award in 1979 for the scary pop-up book Haunted House, which demonstrated his tendency towards the gothic.

Pieńkowski was born in Warsaw to a country squire father and a scientist mother. He was three when the Nazis invaded Poland in 1939, forcing the family to move around Europe before they eventually settled in England in 1946.

In London, he attended the Cardinal Vaughan Memorial school in Holland Park, where he learned Latin and Greek, before going on to King’s College, Cambridge, to study classics and English.

He illustrated for Granta magazine and designed posters for university theatre productions. At the beginning of his career, Pieńkowski was employed to draw live on the BBC children’s programme Watch!, before the book world discovered him.

Along with Meg and Mog and his pop-up books, he is known for his illustrations of fairytales by Perrault and the Brothers Grimm, The Nutcracker, and The Glass Mountain: Tales from Poland.

Fans paid tribute to Pieńkowski on social media following news of his death. The children’s author Christopher Edge wrote: “When I think back to my earliest memories of childhood reading, the Meg and Mog books shine bright. Thank you, Jan Pieńkowski.”

The children’s author and illustrator Shoo Rayner added: “Sad news – Jan Pieńkowski was an inspiration to me when I was starting out.”

The London Review Bookshop posted: “RIP Jan Pieńkowski – Haunted House is one of the best books in the shop, every time a kid comes across it browsing in the children’s section it blows their mind.”