This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Used the 6th circle pattern designed by Viscious-Speed to create a print that can be used for card making or scrapbooking. Save as a PDF file for the best printing option.
Source Lovinglf
A heavy hitter at 400x400px, but lovely still.
Source Breezi
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Prismatic Triangular Background Design Mark II 5
Source GDJ
The image depicts polka dot seamless pattern.
Source Yamachem
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Prismatic Polka Dots 3 No Background
Source GDJ
A seamless pale yellow paper background with a pattern of animal tracks.
Source V. Hartikainen
Prismatic Geometric Pattern Background No Black
Source GDJ
ZeroCC tileable stone texture, edited from pixabay. CC0
Source Sojan Janso
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat