Greece was the site of the first European civilizations, beginning with the Minoans (2600-1450 BCE). By the 5th century BCE, Greece was at a cultural peak that reverberates through western culture to this day.
Since the Greeks were so busy with art, culture, and learning they were an easy take-over target for the Romans in the 2nd and 1st century BCE. When the Roman Empire was split in two, Greece became part of the eastern Byzantine Empire. The fall of the Byzantine Empire in 1453 paved the way for the Ottoman conquest of Greece. The Ottomans ruled Greece until the Greeks rebelled in 1821, finally gaining independence in 1829.
Greece had an on-again off-again monarchy in the first half of the 20th century, and was invaded by Italy in 1940 followed by Germany in 1941. In 1974 the monarchy was abolished by plebiscite and the Hellenic Republic -- the third republic in Greek history -- was established.
Greece on Wikipedia