One old name of Korea is Goryeo (also spelled as Koryŏ).
Goryeo and its Significance
According to the provided reference, Goguryeo (also spelled as Koguryŏ) was also known as Goryeo (or Koryŏ), and this name ultimately became the source of the modern name "Korea". This highlights the historical significance of Goryeo.
Historical Context: Goguryeo
The reference mentions that the 3rd and 4th centuries saw Goguryeo engaged in territorial disputes with the Chinese and Xianbei. These conflicts resulted in both territorial gains and losses.
Modern Korea's Name Origin
The legacy of Goguryeo, through its alternative name Goryeo, persists in the modern name "Korea," demonstrating a direct link to its historical roots.