Did a quick Google, and came up with a speech by the Lt. Gov. of BC...who had this to say about Levées:
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Remarks by
The Honourable Iona Campagnolo, PC, CM, OBC
Lieutenant Governor of British Columbia
New Year‘s Day Levée 2002
Government House
Welcome to 2002!
Thank you for accepting the invitation to attend this Levée at historic Government House. We owe the word but not the practice of the "Levée" to the Sun King Louis XIV who famously set a fashion trend throughout late 17th Century Europe by conducting the business of France on rising from his bed and while still wearing his dressing gown.
Avant le Canada ete une Nation, trois Cent ans passe, a son Chateau,
{translation mine (Gunnar}: Before Canada was a nation, 3 hundred years ago, in his mansion...}
le Gouverneur du Nouvelle France a donnez une grande occasion du bonnes auceuille sur le premier jour de la Nouvel An.
{the governor of New France gave a fancy ball the first day of the New Year...}
Avec le Cheferie des village, les Religieuse, les Commandant Militaire, les Politicien, et les important Homme des Affairs,
{with the village cheiftans (or elders, or otherwise important people like mayors), representatives of the clergy, military command, politicians and important businessmen}
le Gouverneur presenterez les nouvelle de la pays ancienne, et de la colonie, et aussi son opinions politique que ce moment la.
{The governor presented the news of the old country, the colony and also his political opinions of the moment}
En retourn, les honourable visite a rassurez le Gouverneur que leur support continuelle pour le Roi.
{In return, the honourable visitors reassured the governor of their continued loyalty to the King}
Canada’s Levée is a custom of our own. It is firmly anchored in the 17th Century in the earliest days of the Fur Trade with traditions set by the men of the North West Company based in Montreal and the Hudson’s Bay Company headquartered in London. A Levée might begin at 4:00 in the morning with a mighty salvo of rifle fire in the stockade Courtyard, then Senior Officers of the Fur Brigades dressed in their best would pay their respects to the Master of the Fort, who was obliged to returned the compliment with hearty food and drink. "Sang du Cariboo" or in English, "Moose Milk", was the drink of choice. It was an improbable blend of spices, wine, rum or whisky, and goat‘s milk, to which the 20th century added egg-nog and ice-cream! (and as for B.C.‘s Canadian Scottish and Seaforth Highlanders "Athol Brose" you just add honey and oatmeal!)
In the scattered communities of Canada’s early days, the Levée was mandatory, assuring allegiance to the crown, but was also a time to discuss contracts, business prospects and promotions, to exchange news and gossip and to assess the qualities of the coming generation of leaders. It was said that many a future was either secured or dashed subject to processes at a Levée.
With a British Naval Base here since the 1840’s, Levée’s have been a traditional and valued feature of life in Victoria for more than 160 years. Other institutions also celebrate the arrival of the New Year with a Levée, but here on this site, a Levée has been held since British Columbia joined Canada in 1871. Its function has changed little, but its participants have: for example, during the Second World War, women Officers of Canada’s Armed Forces were the first of our sex to be allowed to attend, subsequently the Levée has become fully egalitarian in keeping with our times...."
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So now you can say what one is....it is the formalization of the process of "keeping the troops" (or in this case the people) in the loop as to what is going on with the regiment (country) in return for their continued, *informed* support.
E.g.: Boys, the country needs you right now...here‘s the deal: the economy sucks, the government are thieving swindlers, but the only thing that keeps any remnant of our international prestige alive is the fact that we still have some military clout with which to back up our foreign policy decisions. So, now you know the situation and why we need your continued service. God Save The Queen!
(But stated a lot more formally, with a lot more detail).
