Louis William Wain (5 August 1860 – 4 July 1939) was an English artist best known for his drawings of anthropomorphised cats and kittens.

Wain was born in Clerkenwell, London. In 1881 he sold his first drawing and the following year gave up his teaching position at the West London School of Art to become a full-time illustrator. He married in 1884 but was widowed three years later. In 1890 he moved to the Kent coast with his mother and five sisters and, except for three years spent in New York, remained there until the family returned to London in 1917. In 1914, he suffered a severe head injury in a horse-drawn omnibus accident and ten years later was certified insane. He spent the remaining fifteen years of his life in mental hospitals, where he continued to draw and paint. Some of his later abstract paintings have been seen as precursors of psychedelic art.

Wain produced hundreds of drawings and paintings a year for periodicals and books, including Louis Wain's Annual which ran from 1901 to 1921. His work also appeared on postcards and advertising, and he made brief ventures into ceramics and animated cartoons. In spite of his popularity and prolific output, Wain did not become wealthy, possibly because he sold his work cheaply and relinquished copyright, and also because he supported his mother and five sisters.

Wain's later work, where his cats dissolve into kaleidoscopic abstract patterns, has been identified as an important precursor to 1960s psychedelic art. 

In 1972, the Victoria and Albert Museum devoted a major exhibition to Wain's work.

Wain's life is the subject of The Electrical Life of Louis Wain, a 2021 Amazon Studios production starring Benedict Cumberbatch as Wain and Claire Foy as his wife Emily Richardson.

Bibliography

• All Sorts of Comical Cats. Verses by Clifton Bingham London: Ernest Nister
• Fun at the Zoo with Verses By Clifton Bingham
• Funny Favourites. Forty-five Pen-and-Ink Drawings by Louis Wain. London. Ernest Nister.
• Madame Tabby's Establishment (1886)
• Our Farm: The Trouble of Successes Thereof (1888)
• Dreams by French Firesides (1890)
• Peter, A Cat O'One Tail: His Life and Adventures (1892)
• Old Rabbit the Voodoo and Other Sorcerers (1893)
• Fun and Frolic, with verses by Clifton Bingham, London: Ernest Nister (1900).
• The Dandy Lion (1901)
• Cats (1902)
• Pa Cats, Ma Cats and their kittens (1903)
• The Louis Wain Kitten Book (1903)
• Claws and Paws (1904)
• Mixed Pickles by Louis Wain (c. 1905)
• Cat's Cradle (1908)
• Pantomime Pussies (c. 1908)
• Louis Wain's Cat Painting Book (c.1910)
• Louis Wain's Cats and Dogs (c. 1910)
• The Louis Wain Nursery Book (c. 1910)
• Louis Wain's Cat Mascot (postcard coloring book, c.1910)
• Father Tuck's Struwwelpeter As Seen by Louis Wain, Told in Merry Rhymes by Norman Gale (c.1910), second Edition Fidgety Phil and Other Tales (c. 1925)
• The Happy Family (c. 1914)
• Daddy Cat (1915)
• Little Red Riding Hood and Other Tales (1919)
• Music in Pussytown (c. 1920)
• Somebody's Pussies (1925)
• The Boy who Shares My Name (1926)