Where is telephone country code 1 819?

Telephone country code +1 (dialed as 00 1 from many places) is North America (USA, Canada, etc.). Area code +1 514 is Montréal, Québec, Canada.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)