Conquering the colonies was an almost impossible task. The sheer geographical size of the colonies made it impossible for British forces to occupy the countryside. Because of their inability to control the countryside, the British found it difficult to protect Loyalists from the fury of patriots, who sometimes tarred and feathered and even murdered those who remained loyal to the Crown. The colonies also lacked a single national capital, which, if captured, might end the conflict.
A major British mistake was failing to take sufficient advantage of Loyalists. Before the Revolutionary War began, some 50,000 Loyalists formed nearly 70 regiments to help the British maintain control of the colonies. But British commanders did not trust the loyalists or respect their fighting ability. As a result, the British alienated many potential supporters.
The guerrilla tactics that Americans had learned during Indian wars proved very effective in fighting the British army. Militiamen struck quickly, often from behind trees or fences, then disappeared into the forests. Because many Americans wore ordinary clothing, it was difficult for the British to distinguish between rebels and loyalists.
Washington's strategy of avoiding large-scale confrontations with the royal army made it impossible for the British to deliver a knock-out blow. Only once during the Revolution (at Charleston, S.C. in 1780) did an American army surrender to British forces.
The intervention of France, Spain, and the Netherlands in the conflict made a crucial difference in the Revolution's outcome. It is highly improbable that the United States could have won its independence without the assistance of France, Spain, and Holland. Fearful of losing its sugar colonies in the West Indies, Britain was unable to concentrate its military forces in the American colonies.
All slave societies are highly vulnerable during wartime, and the British recognized that slaves might help them suppress the Revolution. In November 1775, Lord Dunmore, Virginia's royal governor, issued an emancipation proclamation, freeing any slaves or indentured servants willing to serve in the royal army. At least 800 slaves joined Lord Dunmore's forces. But the threat of slave emancipation led many southern slaveholders to support the patriot cause.
Perhaps the single most important reason for the patriot victory was the breadth of popular support for the Revolution. The Revolution would have failed miserably without the participation of thousands of ordinary farmers, artisans, and laborers who put themselves into the line of fire. The Revolution's support cut across region, religion, and social rank. Common farmers, artisans, shopkeepers, petty merchants were major actors during the Revolution. Ex-servants, uneducated farmers, immigrants, and slaves emerged into prominence in the Continental Army.
The colonists had several large advantages that helped them offset the British military advantage. First and most important of these was that the colonists were fighting for their homes and families.
This is what the colonists were facing. So you can see why the colonists were willing to keep fighting even when it appeared they were losing.
The second big advantag was distance. Great Britain was 3,000 miles away. Across the Atlantic Ocean. The British had to bring their army with all its supplies across that ocean. This was a trip that took three weeks to a month in the sailing ships of the time. One month. Think about that. What would your life be like if you asked your parents a question and it took them a month to answer? Or when you asked for a meal and it took them a month to get it to you? This is what the British had to deal with.
The third big advantage for the colonist was other nations. Great Britain did not have a large army. They had a very large Navy, but their army was quite small. So to help out the King hired German soldiers to go and fight in the colonies. These soldiers were called Hessian by the colonists since many of them were from the German province of Hesse-Kassel. These soldiers were paid to fight; this is called being a mercenary (another vocabulary word). The colonists, including those still loyal to England (loyalists or Tories), were angered that the King had hired soldiers who were not even British to fight them.
A fourth advantage was the way of fighting. Colonists fought the way they had fought in the French and Indian wars. They hid behind trees and walls and shot at the British from ambush (a vocabulary word) and cover. The colonists couldn't beat the British in a European type battle (as we have seen - look at Washington's record of Battles Lost), but the colonists always seemed to recover and be back since they didn't lose many men. The British could and did win the battles and capture the cities, but the colonial army was always still there.
A final big advantage the colonists had was allies. The French, Dutch and Spanish all wanted the English to lose. So they gave the colonists all kinds of help. Finally the French actually declared war on Great Britain and formally joined with the colonies in their fight. This led to the great victory at Yorktown.