E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Your health. The story is that Vortigern was invited to dine at the house of Hengist, when Rowena, the hosts daughter, brought a cup of wine which she presented to their royal guest, saying, Was hæl, hlaford cyning (Your health, lord king). (See WASSAIL.)
William of Malmesbury says the custom took its rise from the death of young King Edward the Martyr, who was traitorously stabbed in the back while drinking a cup of wine presented to him by his mother Elfrida.
Drinking healths. The Romans adopted a curious fashion of drinking the health of their lady-loves, and that was to drink a bumper to each letter of her name. Hudibras satirises this custom, which he calls spelling names with beer-glasses (part ii. chap. 1).