Poland
What the source says
Referenced, awaiting primary-source reviewOfficially adopted on 1 August 1919. The colours [are] the White Eagle of Poland [and] a red shield; they are of heraldic origin and derive from the tinctures of the coats of arms of the two constituent nations of the Polish-Lithuanian Commonwealth.
Referenced, not verified: a secondary work states this, and the document that constitutes the flag has not been read for this entry. What the marks mean.
Colors and meaning
Symbolism and history(r1)
A plain white-over-red bicolor of heraldic origin, its colours the tinctures of the arms of the two nations of the Polish-Lithuanian Commonwealth, officially adopted on 1 August 1919.
Most similar flags
The 6 closest of the 194 other national flags, ranked by a similarity index computed from the flag images themselves. The number is that index, 0–100 — not a claim that the two flags are “X% identical”.
- Indonesia90
the same horizontal band layout; near-identical colour proportions.
- Monaco90
the same horizontal band layout; near-identical colour proportions.
- Singapore88
the same horizontal band layout; near-identical colour proportions.
- Chile87
the same horizontal band layout; near-identical colour proportions.
- Lebanon87
the same horizontal band layout; near-identical colour proportions.
- Austria83
the same horizontal band layout; near-identical colour proportions.
From this entry, not from the index: The exact reverse of Indonesia's flag, and, but for a hoist-side blue triangle, identical to the Czech Republic's flag.
Computed at build time: each flag is rasterised to 64x48, and the score is 0.55 × colour overlap + 0.45 × structure. A different weighting would rank these differently. How the index works.
References — not verification
(r1) Referenced to Flag of Poland (Wikipedia (English)) on 2026-07-17. States the adoption year, which colors the flag has, what the colors mean and the symbolism and history on this page. The passage it states them in is quoted at the top of this entry.
Further reading: Flag of Poland on Wikipedia