In all three cases, the competition ended with the winning flag being chosen from a final shortlist of six designs.
Before 1945 the county council used an unofficial coat of arms consisting of a gold shield bearing a blue eagle.
All four of the new 1974 county councils received grants of complete "achievements" of arms consisting of a shield, crest and supporters.
On 1 April 1986 the two metropolitan county councils in Yorkshire were abolished under the Local Government Act 1985.
Supporters: Upon a compartment of a heather moor proper on the dexter a lion Or holding in the sinister forepaw a sword argent hilt pomel and quillons gules and resting the sinister hindpaw on a fountain on the sinister a lion Or holding in the dexter forepaw two keys in saltire argent and resting the dexter hindpaw on a serpent coiled proper.
In the background of the shield are narrow green and blue waves representing the Yorkshire Dales and Wolds.
A number of symbols were added for heraldic difference: crossed keys for the archdiocese of York, the sword borne before the Lord Mayor of York, a serpent for St Hilda of Whitby and a heraldic fountain for the county's coats and waterways.
[18] Granted 22 August 1975 The arms featured a W-shaped pattern and white rose to represent "West Yorkshire".
The black diamonds represented coal mining and the red and silver zig-zag pattern steel processing: on top of these were placed white roses.
The green and gold stripes of the shield represent the wealth generated by the land of the East Riding.