17 Dec 1814 – Fifty British skiffs, each armed with a small cannon, attacked and captured five American gunboats becalmed in Lake Borgne, east of New Orleans. This allowed the British to begin transporting soldiers across the lake.
23 Dec 1814 – Jackson was notified at about noon on 23 Dec that 1,800 British soldiers occupied the Villere Plantation, eight miles south of New Orleans. Jackson did the unthinkable and attacked them that night. The attack was initiated by the USS Caroline, which fired grapeshot point-blank into the British camp. He almost defeated them, but was stymied by the continuous flow of British soldiers from the east.
24 Dec 1814 to 17 Jan 1815 – American soldiers, especially the Choctaws and Tennessee militia, conduct nightly hunting parties to kill British sentries. The British were outraged, and complained to Jackson about this “barbaric” behavior. Jackson reminded them that they were the invaders, and the nightly slaughter continued until the British left.
28 Dec 1814 – British attacked the American position that Jackson began constructing the morning of 24 Dec, about a mile north of the Villere Plantation. American artillery quickly disabled the few British cannons and the British retreated.
1 Jan 1815 – British attacked the (much stronger) American position again, using more artillery that they laboriously dragged through the swamps. The Americans were conducting a New Years Day parade, and were caught by surprise. The Americans recover quickly, and within three hours the British artillery is destroyed. The British retreated.
8 Jan 1815 – British attacked the (very much stronger!) American position again, using even more artillery that they laboriously dragged through the swamps. The Americans quickly disabled the British artillery, and the British attacked with Infantry. Cannon and musket fire devastated the British Infantry, slaughtering many soldiers and officers. An attack up the west bank of the Mississippi succeeds, but is recalled by British leadership reeling from the impact of the slaughter on the east bank. The British retreated. This is the battle we think of as The Battle of New Orleans.
9-17 Jan 1815 – British, unwilling to give up the enormous booty of New Orleans, bombarded Fort St. Philip, the American fort seventy miles south of New Orleans that is blocks British warships from ascending the Mississippi. The fort, commanded by Major Walter Overton, refused to surrender.
18 Jan 1815 – British depart Louisianna.
The importance of these victories is often understated. The Treaty of Ghent, to end the War of 1812, was signed in Belgium on 31 Dec 1814. However, it was not ratified by America until about 17 February, 1815. The war ended the day it was ratified, not the day it was signed.
Had Britain captured New Orleans they would have, at the very least, taken everything in the city as plunder. More likely, they would have kept the city and controlled all trade on the Mississippi. However, it is quite possible they would have attacked north, up the Mississippi, and seized the Louisiana Purchase. Had this happened, America, as we know it today, would not exist.
For the British perspective, read The Campaigns of the British Army at Washington and New Orleans 1814-1815 by Gleig. Gleig was an Infantry Lieutenant, serving with the British Army at Washington and New Orleans, and later became the Chaplain General of the British Army. This was not a good time to be British.