Statistics for occurrence #1 of “Nicaragua” in entry central-america of Harper's Encyclopedia of United States History:
...in recent years to bring about a federation of the five republics, the latest in 1895, when the Greater Republic of Central America was formed, and in 1898, when, by treaty, Honduras.
Salvador, and Nicaragua formed the United States of Central America, Guatemala and Costa Rica declining to enter the compact.
Local revolutions and mutual jealousies have so far prevented a permanent union.
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