A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
Abstract Tiled Background Extended 8
Source GDJ
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
A seamless paper background colored in pale yellow.
Source V. Hartikainen
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Continuing the geometric trend, here is one more.
Source Mike Warner
Almost like little fish shells, or dragon skin.
Source Graphiste
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
We have some linen patterns here, but none that are stressed. Until now.
Source Jordan Pittman
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Colorful Floral Background 3 No Black
Source GDJ
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
From a drawing in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin