A common factor observed in many biographies of the early Americans was that they "sailed to America from Leyden, Holland". Often, they left their native country and went to Leyden, and from there, commenced to America. I assumed it must have been a port city with vessels departing for the "New World" on a daily basis, but there is more to the story.
The year 1568 marked the beginning of the Dutch War of Independence, or The Eighty Years' War. Seventeen Provinces under the control of Philip II of Spain, revolted against his rule. They were the people of the Netherlands, Belgium and Luxembourg. Philip responded swiftly, regaining control over most of the rebelling provinces, resulting in the death of an estimated 100,000 of the Dutch and many of his own in the process. The northern provinces, however, were able to successfully resist and in 1581 formed the Republic of the Seven United Netherlands. The war continued until 1648, when a treaty was finally drawn and the Dutch Republic was officially recognized as an independent country.
Leiden (often spelled Leyden) was one of the provinces that successfully resisted, during what is called the "Siege of Leiden", in 1574, and had become a place known for its strength and security. In a time when millions of Protestants were being murdered because of their refusal to convert and comply with the Roman Catholic Church, Leyden welcomed the persecuted and was a place of sanctuary for countless refugees, many of whom were from Wallonia, southern Belgium. The Walloon Church at Leyden, shown below, was formed in 1584. One of my ancestors, Daniel Tourneur, fled to Leyden from Picardy, France, and had his first son baptized at this very church in 1651. Two years later, he set sail for New Amsterdam (now New York). Another ancestor, Frederick de Vaux, was a Protestant Walloon who suffered "severe persecution" causing him to flee (possibly from France) to Mannheim, Germany, and from there he sailed to England before coming to America.
Sources:
"Revised History of Harlem (City of New York): Its Origin and Early Annals", by James Riker, Henry P. Toler, and Sterling Potter, 1904.
Eighty Years' War article on Wikipedia
Siege of Leiden article on Wikipedia