<span>They had civil wars supported by foreign countries.</span>
The Germans sank a British ship which had American passengers. This was the first step. After this due to the unrestricted submarine warfare more US ships were sunk by German U-boats.
If you would have lived in Greece in about 300BC, you could have witnessed The battle of Thermopyle
Sunken Phoenician ships have been discovered from the deep Mediterranean waters near Ashkelon, in modern-day Israel, to the Spanish shoreline.
