Christina Haycock, 49, of Mold, Flintshire, caused council offices and courts to be evacuated, Caernarfon Crown Court was told.
She admitted making a bomb threat to Flintshire council on 22 January.
Defence counsel Jade Tufail said she wanted an apology "from those who were supposed to protect her at the time".
The court heard Haycock, a criminology and criminal justice graduate who had been in care from the age of three, told a council phone operator: "Shire Hall has got a bomb in it so I would tell them to get out."
Prosecutor Elen Owen said the call caused council staff, judges, magistrates and other court users in Mold to be evacuated with an estimated cost of tens of thousands of pounds.
Judge Philip Harris-Jenkins said: "In the circumstances of this case, because of the gravity of the offence, the disruption it caused, I am afraid I am not going to be in a position to suspend the sentence."
A woman who made a bomb hoax call because she wanted a council to apologise for her treatment as a child in care has been jailed for a year.