The date at the end of the post is not possible. Teddy Roosevelt died in 1918.
No he didn't.
Rep. Tancredo’s website has the quote in 1907 ...
BTW: Died: January 6, 1919 in Oyster Bay, New York
Theodore Roosevelt indeed wrote these words....The passages were culled from a letter he wrote to the president of the American Defense Society on January 3, 1919, three days before Roosevelt died.
"Americanization" was a favorite theme of Roosevelt's during his later years, when he railed repeatedly against "hyphenated Americans" and the prospect of a nation "brought to ruins" by a "tangle of squabbling nationalities."
He advocated the compulsory learning of English by every naturalized citizen. "Every immigrant who comes here should be required within five years to learn English or to leave the country," he said in a statement to the Kansas City Star in 1918. "English should be the only language taught or used in the public schools."
He also insisted, on more than one occasion, that America has no room for what he called "fifty-fifty allegiance." In a speech made in 1917 he said, "It is our boast that we admit the immigrant to full fellowship and equality with the native-born. In return we demand that he shall share our undivided allegiance to the one flag which floats over all of us."
Just to inform you - Teddy Roosevelt died in 1919 not 1918 as you wrote.