I assume the phrase refers to the Colonial army. As the war progressed the army became better trained and somewhat better equipped, but perhaps "ragtag" still applied. They were certainly a band of rebels.
One definition is: A ragtag army is a disreputable or disorganized group.
We must unite our ragtag forces if we are to succeed against the imperialist army!
The Rebels were the South. They fought against the North, i.e. the Union army.
I can whip this ragtag crew into shape pretty quickly. The ragtag band impressed all who were present.
Rebels
The Rebels.
Johnny Rebels NEW RESPONDENT The Confederate Army (CSA Army)
This was because at that time, the colonies had no professional full-time army to do battle; it was made up of civilian volunteers, most farmers and uneducated.
'the union' and the southern was 'the rebels'
Confederate army was the name. They were also called Rebels too.
Von Seeckt