Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Prismatic Polka Dots Mark II No Background
Source GDJ
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Remixed from a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks. https://cloaks.deviantart.com
Source Atle Mo
Abstract Tiled Background Extended 8
Source GDJ
Nice and simple crossed lines in dark gray tones.
Source Stefan Aleksić
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin