A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
This seamless pattern consists of a blue grid on a yellow background.
Source V. Hartikainen
Never out of fashion and so much hotter than the 45º everyone knows, here is a sweet 60º line pattern.
Source Atle Mo
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
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
Lovely pattern with splattered vintage speckles.
Source David Pomfret
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
Similar to original, but without gaps in between the arrows. This seamless pattern was created from a rectangular tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
Sharp pixel pattern, just like the good old days.
Source Paridhi
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
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
Inspired by a drawing in 'Poems', James Smith, 1881.
Source Firkin