From a drawing in 'Two Women in the Klondike', Mary Hitchcock, 1899.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Prismatic Polka Dots 3 No Background
Source GDJ
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
Seamless Green Tile Background
Source V. Hartikainen
Oh yes, it happened! A pattern in full color.
Source Atle Mo
Prismatic Geometric Pattern Background No Black
Source GDJ
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Almost like little fish shells, or dragon skin.
Source Graphiste
Zero CC tileable brick texture, photographed and made by me. CC0
Source Sojan Janso
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
A black tile-able background with paper-like texture.
Source V. Hartikainen
A bit strange this one, but nice at the same time.
Source Diogo Silva
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman