St. Patrick's blue

St. Patrick's blue is a name applied to several shades of blue associated with Saint Patrick and Ireland. The colour blue's association with Saint Patrick dates from the 1780s, when it was adopted as the colour of the Anglo-Irish "Order of St. Patrick". In British usage, it refers to a sky blue used by the Order of St. Patrick, whereas in Irish usage it is often a dark, rich blue. While green is now the usual national colour of Ireland, St. Patrick's blue is still the official colour of state. St. Patrick's blue is still found in symbols of both the state and the island.

The Order of St. Patrick was established in 1783 as the senior order of chivalry in the Kingdom of Ireland. The colour of its honours needed to differ from those of the Order of the Garter (dark blue) and the Order of the Thistle (green). Orange was considered, but the association with orangeism felt to be too sectarian, so the lighter blue of the arms of Ireland was chosen. Knights and officers of the order wore a "sky blue" mantle and riband, a hat lined with "blue", and a badge ringed with "blue" enamel. The name "St. Patrick's blue" was common but never officially used by the Order. The exact shade of blue used varied over time. A sky blue tinged with green was used by Lord Iveagh in 1895 and confirmed in 1903.

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