Why Japanese Udon Noodles named like this? And why Pampkin in Japan named Kabocha?

Why Japanese Udon Noodles named like this? And why Pampkin in Japan named Kabocha?

Why the Japanese forget Udon Noodles, Pampkin or Kabocha?

Udong was the seat of Cambodian kings from 1618 to 1866.
Phnom Udong, “Hill of the Victorious” from phnom “hill”. It was the capital between 1618 and 1866.
Udong is the former capital of Cambodia. The name Udong, often also spelled "Oudong", means "victorious". It was the former capital of Cambodia from 1618 to 1866, after the Khmers shifted from Angkor, and before the capital moved again, to Phnom Penh. It is a place that the Thais have plundered, the Americans have bombed and then finally the Khmer Rouge has blown up.
Japanese Udon Noodles
Udon are white and the thickest noodles Udon noodles are made by kneading wheat flour, salt, and water. Udon can be eaten hot or cold and can be cooked in many ways. You might have seen udon noodles in hot soup. Cold udon noodles are also popular in summer. Cold udon noodles are eaten by dipping into dipping sauce.
Khmer noodle (Num BonhChok)
Num Bonhchok - Rice vermicelli noodles with raw vegetables. There are two different soups that can accompany this dish, a green or red soup. The green soup is made of ground fish, lemon grass, and kroeung (Samlor Khmer). Prahok is used with a green soup. The red soup is made from tenderized chicken and a simple coconut curry (Samlor Kari).
Num BonhChok from Kampot province is different from Num BonhChok from other parts of Cambodia. Kampot inhabitants use distinctive ingredients to the thick noodle. Those are: tiny saltwater shrimp, bean sprout, coconut cream, peanut and fish sauce.

Pumpkin
It is generally believed that all squash originated in Mesoamerica, but may have been independently cultivated elsewhere, albeit later. The kabocha, however, was introduced to Japan by Portuguese sailors in 1541, which brought it with them from Cambodia. The Portuguese name for the pumpkin, Cambodia abóbora (カンボジャ・アボボラ), was shortened by the Japanese to kabocha. Certain regions of Japan use an alternate abbreviation, shortening the second half of the name instead to "bobora". Another name for kabocha is 南瓜 or 南京瓜 (Nanking melon), which suggest that the vegetable arrived in Japan by way of China (1).
In Cambodia, people plant pumpkin nearly everywhere. As one of the most popular crops in Cambodia, pumpkins are very versatile in their uses for cooking, from the fleshy shell, to the seeds, to even the flowers; most parts of the pumpkin are edible. The leaves, the male flowers of the pumpkin plant are consumed as a cooked vegetable or in soups (Samlor Korko, Samloor Proheu). The small pumpkins are steamed with custard inside and served as a dessert. Cambodia people made a little shredded of pumpkin flesh mixed with rice flour and wrapped with banana leave, are steamed and used as a cake. Pumpkin seeds, also known as pepitas, are small, flat, green, edible seeds.

When the delegation of Kingdom of Cambodia at Sangkum Reas Niyum in decade 1960s visited the Japan, they always prepared food from pumpkin and noodles for Cambodian delegates. The government personal of Japan said in front of delegation of Kingdom of Cambodia like this “We prepare the noodles and pumpkin for food for you because the Japanese brought them from Cambodia at the time of Udong, so the noodle the Japanese called Japanese Udon Noodles and the pumpkin named Kabocha from the word Kampuchea” (2).

References:
1. Wikipedia, the free encyclopedia.
2. Kampuchea journal at decade 1960.