The Mogamigawa has its origins on the slopes of Mt. Azuma on the border between Fukushima and Yamagata. Thus, when Basho speaks of it originating in Michinoku, this is not entirely accurate, but he means that it begins in the mountains of the remote north country. We find mention of this river in the Kokinshu: Mogamigawa/ noboreba kudaru/ inabune no/ ina ni wa arazu/ kono tsuki bakari. In the Senzaishu we find: Mogamigawa/ mizu kasamasarite/ samidare no/ shibashiba kari mo/ harenu sora kana.

Goten is the name of the river rapids at a place where the river is dotted with rocks like the stones of a Go board. This is regarded as one of the three rough spots on the Mogami River.

Hayabusa is another of the three difficult rapids. Basho says these places are downstream from Oishida, but actually they are up the river. Basho never actually saw these places, but he heard about them from others.

Itajikiyama rises 630 meters above sea level and is often used as a pillow word. As one floats down the river, this mountain can be seen in the distance. It forms the leading edge of the Gassan massif. Apparently this is a foreshadowing of what is to come at Gassan. At the same time the peril of the river passage is an echo of the peril of the mountain crossing made earlier from Dewagoe to Obanazawa.

Sakata is a commercial port at the mouth of the Mogami River. This port was established in the 1660s by Kawamura Tamayoshi who opened the western sea routes. Sakata became a transportation center for benihana and for rice from the Shonai plain. It became one of the nation's leading commercial centers. It was an important link in the trade route between Kansai and Hokkaido. Basho uses it here to balance his earlier reference to the port of Ishinomaki on the Pacific side of Japan.

Inabune are a type of boat unique to the Mogami River, they are long and narrow and are used for transporting the harvested rice. Rice plants are called ina hence the name. One local gazateer, Dewa Fudoki Ryaku published in 1762 says that the waves and current of the river cause the long, thin boats to flutter on the water. The word for the negative expression 'no' in Japanese is ina and is often signified by waving the hand in a fluttering movement. Thus the boats are called inabune. A reference to these boats is found in the Kokinshu #1092: Mogamigawa/ noboreba kudaru/ inabune no/ ina ni wa arazu/ kono tsuki bakari. ("Boats go up and down the river/ Mogami, loading rice./ Enjoying the view, pray, wait a month-/ be sure I love you true." H.H. Honda. L.R Rodd gives this translation: As the rice boats ply/ the Mogami River they/ pole upstream and back -/ you too should come again it's/ only this month I say no." Rodd adds this note: "Lines 1-3 (of the rice boats that row up and come back down the Mogami River) are jo linked to the kakekotoba ina (rice; no)." ).

Shiraito no taki is located on the north bank of the river; facing it across the river is Kusanagi Hot Springs. Of the 48 waterfalls along the course of the Mogami River, this is the tallest and most beautiful, falling some 220 meters. It is used as a pillow word for poetry. A couple of Yoshitsune's poems on this waterfall are found in Gikeiki.

The reference to the green leaves (aoba) is an engo linked with the white of shiraito.

The Sennindo is actually located upstream from Shiraito Falls. It is dedicated the worship of the priest Hitachibo Kaison who was a retainer of Yoshitsune. Following Yoshitsune's death, Kaison lived on and travelled around the country and eventually became a sennin or wizard and lived to be very old. According to Ihara Saikaku's Saikaku Shokoku Hanashi, vol. 1, Kaison was still alive in 1615. The mountain behind the temple is lushly overgrown with trees and is particularly quiet and isolated. In the river in front of his hall is a pool called Sennin Pool which is known as a difficult place on the river.

THE POEM: Samidare... The season word is samidare indicating summer. This refers to the rainy season which came in the fifth month of the lunar calendar. The idea is that the river is full and running fast; the poem gives a good sense of the power and speed of the river. Basho originally wrote this poem at Oishida at the home of Ichiei. His first version read: Samidare wo/ atsumete suzushi/ Mogamigawa. Before he got on the boat, the river must have seemed cool and refreshing as he viewed it. By using the adjective suzushi, cool, the poem could also serve as a greeting to his host Ichiei. This was the opening verse for the linked verse series he and others composed in Oishida. Ichiei followed with the lines "Kishi ni hotaru wo tsunagu shuko." Here he likens Basho to the fireflies and sings about his wish to interrupt the voyage. After boarding a boat on the river, however, this characerization of it seemed too tame and sluggish, so Basho changed it to the much more dramatic hayashi meaning fast. By changing this one word he has changed the whole experience from observing the river to a much more involved riding the river. Hayashi not only means that the river is fast, it also suggests that Basho's heart is beating fast. A work called Toyu Zatsuki says that this is the fastest river in the world, and that its flow is like a waterfall with mountains closing in on both sides. This is just the impression of the river Basho gives in his poem. The poem also gains power because he uses the transitive verb atsumete rather than the intransitive atsumatte.; thus the river is a living thing that brings the water together, not just an anonymous phenomenon of nature. There is no longer the objective distance of the observer, the poet gives us his involved experience. Aso also says that if he had written hayaki instead of hayashi it would have made the poem merely descriptive. This poem may be based on an earlier one found in Kenko Kashu: Mogamigawa/ hayaku mo masaru/ amagumo no/ noboreba kudaru/ samidare no goro. Whether or not Basho had this earlier poem in mind, he clearly makes his own poem reflect his experience. Basho's poem expresses his sense of the granduer of the river.

Basho arrived at Oishida at two-thirty on 5.28 (7.14) and stayed at the home of Takano Ichiei. The following day they began to compose a sequence of verses and later went to visit a nearby temple. On the 30th they resumed work on their poetry sequence and again spent the night with Ichiei. On 6.1 they set out at eight o'clock accompanied by Ichiei as far as Amido. They went on to Funagata by horseback, and then walked on to Shinjo.

At Shinjo on 6.2 they were invited to the home of Shibutani Morinobu (Kurobei) where a group composed a poetry sequence. At that time Morinobu was the wealthiest and most prominent man in Shinjo. In one of the poems of the sequence Basho makes reference to the pure waters of the region. This reflects his sense of poetic responsibility. One ancient legend tells of how a poet came here and wrote a poem about the pure water, but the poem was such a poor one, the water turned muddy. Basho wanted to keep both the water and the poetry pristine.

Basho says only that they waited at Oishida for the weather to clear and does not mention their stay at Shinjo. Having already celebrated their poetry composition at Oishida, he now wants to focus his attention on the Mogamigawa.