Origin of Auspicium Melioris Aevi

Question

Auspicium Melioris Aevi, commonly translated to “Augur/Omen/Hope of a Better Age” serves as the motto of the Order of Saint Michael and Saint George.

Does it have any ancient origin? Or is it's originator known?

Answer 1

I haven't been able to find Ancient or Classical quotations:

You mention "Hope of a better Age."

Spes Melioris Aevi is the Motto of Rees in heraldry from the time of Richard I 'Lionheart.' And Spes Melioris Vitae 'Hope of a Better Life,' the Motto of the Broughtons.

"Herald of a better age" "Forerunner of a better Age" occurs in an inscription recorded in “Recueil général des inscriptions… Charles VI to Coronation of Francois I" (published 1745)

The Coronation of Maria Theresa, in Prague, 1743, was heralded as Prodromae melioris Aevi, a “Token of Tranquility restored… forerunner of a better Age, to the public joy of the people."

Finally,

Auspicium melioris aevi is the Title of a satirical print (now in the British Museum) showing the Prime Minister, Pitt, after the debate 5 March 1787 on the Declaratory Bill.

The coloured print is lettered: 'Pubd Marh 17 1788 by S W Fores N° 3 Piccadilly.' The loss of the American Colonies was followed by trouble on the Madras coast.

As a Motto for the Order of St Michael and St George, the Prince Regent had George III's ill health and madness to worry about, but victory at Trafalgar, Quiberon Bay, and Waterloo could be read as 'Auguries of a Better Age.' George III died two years after the Order was founded.

Answer 2

It is already found with this wording, but in plural, Auspicia melioris aevi, in a treaty of Dutch colonizers and the Iroquis, the Tawagonshi Treaty of 1613.