US 19th century territory acquisitions

ANKARA

The U.S. has acquired some eight territories including Texas, Alaska and California since 19th century.

The administration of U.S. President Donald Trump has informally asked Danish officials to sell semi-autonomous Greenland, the world's largest island, to the U.S., however, Denmark rebuffed the "absurd" offer.

Trump was not the first president to eye purchasing Greenland. There were two other failed attempts -- first in 1867 and then in 1946.

Greenland is on the radar of U.S., Russia and China, ever since global warming has been taking a toll in the Arctic by melting ice masses and allowing deeper penetration into the island's vast natural resources.

The following acquisitions in the U.S. history shed light to Trump's interest in a new major "real estate deal."

1803: Louisiana

Purchased from France for $15 million, comprising 23.3% of the current territory of the U.S.

1818: Red River Valley

Following the declaration of the Anglo-American Convention, which established the official U.S.-Canada border, the land was secured at no cost.

1819: Florida

Spain ceded all of East Florida to the U.S. and gave up its claims to West Florida.

1845: Texas Annexation

Broken away from Mexico, 389,000 square miles (626,000 kilometers) of territory was annexed by the U.S.

1846: Oregon Treaty

Establishing the boundary between Canada and the U.S., the Oregon Territory, totals 286,000 square miles (460,000 square kilometers), added to America.

It includes present-day states of Oregon, Washington, Idaho and portions of Montana and Wyoming.

1848: Mexican Cession

Ceded by Mexico following the Mexican-American War.

It includes all of present-day states of California, Nevada, and Utah, as well as the portions of Arizona, Colorado, New Mexico and Wyoming.

1853: Gadsden

Purchased from Mexico for $10 million and gave the U.S. possession of parts of New Mexico and Arizona in the Mesilla Valley south of the Gila River.

1867: Alaska

Oil-rich land purchased from Russia for $7.2 million.