Artistic licence in period settings often works well, but with Frontier the time period has been ignored completely. From the poorly written dialogue and clichรฉ English villains (if the British armed forces were as undisciplined as this, they'd never have got as far) to the hilarious inaccuracy of the costumes and hair, this is a mess. To dwell on the costume design, it's just so bad - clothes centuries later have been used with barely a nod to the period, whilst most female characters are reduced to a ballooning dรฉcolletage by absurdly low cut dresses.
If you want late Eighteenth century drama that's well produced with decent writing, watch Turn - compelling and pays respect to actual events, which Frontier appears to treat as an inconvenience.