The image depicts a seamless pattern of pine tree leaves.
Source Yamachem
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
The edges of all the red objects line up either vertically or horizontally, but it doesn't appear so. Made from a square tile that can be got by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
From a drawing in 'Picturesque New Guinea', J Lindt, 1887.
Source Firkin
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
The tile can be had by using shift+alt+i on the selected rectangle in Inkscape
Source Firkin
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
Background formed from the original with an emboss effect
Source GDJ