At erst

at first; at the beginning.

See also: Erst

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
This is a food wine of the highest order and was a very nice match for marinated anchovies at Erst.
Though at Erst glance the portraits seem an obvious pair they may not have been painted as such - Henrietta Maria sat for Van Dyck no fewer than 25 times between 1632 and 1640.