During this decade, former Georgia governor George Mathews asked the slave Tony Proctor to garner native support for a war against Spain, but Proctor used a native language to warn chiefs not to trust the US. Early in this decade, some plantation owners invaded Amelia Island and declared the Republic of East Florida. The ambiguously worded Article Nine of a treaty signed in this decade enabled the US to take over native land which was formerly a British-backed buffer zone in the west. At the end of this decade, (*) Florida was ceded to the US in the Adams-Onís treaty. In this decade, the Creek confederacy was forced to give up much of Alabama by Andrew Jackson. (10[1]-5[1])For 10 points, in which decade was the Treaty of Ghent signed just before the battle of New Orleans? ■END■ (10[1])