John Ericsson (July 31, 1803 – March 8, 1889) was a Swedish inventor and mechanical engineer who was born in Värmland, Sweden, but helped change the face of the United States of America.

John's father Olof Ericsson worked as 'director of blastings' during the excavation of the Swedish Göta Canal. While working with his father and brother John's extraordinary skills were discovered by Baltzar von Platen, the architect of the Göta Canal project. John was inducted into the Swedish Royal Navy and engaged as a trainee at the canal enterprise. At the age of fourteen, John worked independently as a surveyor. He was so young that his assistant had to carry a footstool for him to reach the instruments during surveying work.

At the age of seventeen John joined the Swedish army in Jämtland, serving in the Jemtia Field Ranger Regiment, as a Second Lieutenant, but was soon promoted to Lieutenant. While surveying in northern Sweden, John constructed a revolutionary heat engine which used the fumes from the fire instead of steam as a propellant. Although the design was flawed in its use of birch rather than coal as a heat source, John's reputation began to grow throughout Europe.

After leaving the Swedish Army, John moved to England where he improved the standard ship design with two screw-propellers moving in differing directions. Although, the Admiralty disapproved of the invention, an American captain named Robert Stockton took notice of the young inventor.

Stockton encouraged Ericsson to bring his invention to the United States, as it would be better received. As a result, Ericsson moved to New York in 1839. Stockton's plan was for Ericsson to oversee the development of a new class of frigate with Stockton using his considerable political connections to grease the wheels. Upon the election of President Tyler funds were allocated for a new design for a 700-ton sloop. The sloop eventually became the USS Princeton, named after Stockton's hometown.

The ship took about 3 years to complete and was the most advanced warship of its time. In addition to twin screw propellers, it was originally designed to mount a 12-inch ML gun on a revolving pedestal. The gun had also been designed by Ericsson and was the first gun to use the hoop construction method that pre-tensioned the breech adding to its strength and safely allowing the use of a much larger charge. Other innovations on the ship design included a collapsible funnel and improved recoil systems for the guns.

Stockton began to grow weary of the new fame that Ericsson began to receive throughout the construction of the new ship. He avoided letting outsiders know that Ericsson was the true brains behind the design, taking as much credit for himself.

When the ship was initially launched it was a tremendous success. On October 20, 1843 USS Princeton won a speed competition against the steamer SS Great Western, which had until then been regarded the fastest steamer. Unfortunately, during a demonstration firing one of the guns designed by Stockton, the breech broke killing the US Secretary of State and the Secretary of the Navy, as well as six others. Stockton deflected the blame onto Ericsson, ending their friendship.

Ericsson was not discouraged. He proceeded to invent the "hot air engine" in 1852 which used hot air instead of steam as a propellant, probably inspired by his earlier attempts of fume heat engines in Sweden. Ericsson was awarded the Rumford Prize in 1862 for this achievement. Already on September 26, 1854 Ericsson presented Napoleon III of France with drawings of iron-clad armored battle ships with a dome-shaped gun tower, and even though the French king praised this invention, he did nothing to bring it to practical application.

When the American Civil War broke out, the Southern states quickly began developing an ironclad based on the hull of the Merrimack which had been burned before the naval base at Norfolk had been capture. The United States Congress addressed this issue in August 1861 and recommend that armored ships be built for the Union Navy. At this moment, Ericsson presented drawings of the USS Monitor a totally unique and novel design of armored ships, which after much controversy was eventually built and finished on March 6, 1862. The ship went from plans to launch in approximately 100 days, an amazing achievement.

At this moment the Southern ironclad CSS Virginia was harvesting victories against the Northern fleet until the Monitor appeared. A battle on March 9, 1862 at Hampton Roads in Virginia, ended in a stalemate between the CSS Virginia and the Monitor, saving the Northern fleet from defeat. After this numerous monitors were built, and are believed to have considerably influenced the victory of the Northern states. Many basic design elements of the Monitor were copied by future ship designers.

Later, Ericsson worked with torpedo inventions, in particular the Destroyer torpedo boat, and in the book Contributions to the Centennial Exhibition he presents the so-called "sun engines", using solar power as propellant for a "hot air engine". At this time, he was once again bitter and plagued by economic difficulties, and his invention of the solar engine would not have practical applications for another 100 years.

The John Ericsson Republican League of Illinois found its inception among American citizens of Swedish extraction who supported the cause of good government, justice for all men, the spirit of freedom and the principles of the Republican Party.

Initially active among like minded citizens in several counties in Illinois, the current structure of the League first manifested itself in the formation meting held at the Grand Pacific Hotel in Chicago on December 4, 1894. In that same month the organization was incorporated under the name of the Swedish-American Republican League of Illinois.

The first annual convention of the League was held in Chicago March 9, 1895. Since 1904 it has been custom to hold this convention in the city in which the president resides. In 1918 the name of the League was changed to the John Ericsson Republican League of Illinois, honoring the noted Swedish-born American inventor and patriot.

The League is comprised of member chapters throughout Illinois. Its activities have earned it the respect of the Republican Party throughout the country, and its conventions have been attended by two Presidents and innumerable national and international civic leaders. The conventions are usually held on or near March 9th of each year to commemorate the great contribution to freedom made by Captain John Ericsson. It was on that date in 1862 when his inventive genius gave the Union a portentous victory by the ironclad Monitor at Hampton Roads.

The League is now comprised of Republicans of Scandinavian descent in chapters across the state. Its goals remain steadfastly oriented on freedom and justice, accompanied by a respect for the Scandinavian heritage of all its members.