Aoe Moritsugu

The Essence of Ko-Aoe: The Artistic World of Moritsugu

Aoe Moritsugu was a master swordsmith of the Aoe school, active in the mid-Kamakura period, around the mid-13th century, in Bitchu Province (present-day western Okayama Prefecture). The Aoe school was a community of swordsmiths centered in Aoe, Bitchu Province, which lay immediately east of Bizen (in present-day Mabi, Kurashiki City, Okayama Prefecture), and its history spans a long period from the late Heian period through the Nanbokuchō period. The swords of the Aoe school are also called "Ko-Aoe" (old Aoe), and are renowned for their distinctive beautiful *kitae* (forged surface pattern) and *nie-deki* (nie-formed) *hamon* (edge pattern). Moritsugu was one of the master craftsmen representing the golden age of Ko-Aoe and an outstanding swordsmith whose works are highly regarded as supreme-grade creations.

The mid-Kamakura period when Moritsugu was active was a time of stability under the Hōjō regency system, and also an era of mature samurai culture. Around the time of the Mongol invasions (1274 and 1281), Bitchu Province played an important role as a rear area in resistance against the Mongols, and the demand for swords was increasing. The swordsmiths of the Aoe school, including Moritsugu, possessed a distinct technical system different from their counterparts in Bizen, and continued to supply high-quality swords to the samurai society of western Japan.

The Distinctive Kitae of Ko-Aoe: The Mystery of "Sumihada"

The most notable aspect of Moritsugu's works is the distinctive beautiful *kitae* characteristic of Ko-Aoe. The *kitae* of Ko-Aoe possesses a distinctive clarity also called "sumihada" (clear skin) and displays varied, richly patterned surface texture where *itame* and *masame* (wood-grain patterns) intricately intermingle. This characteristic of the *kitae* is clearly distinct from other schools of the Bizen tradition (Osafune and Ichimonji), instead possessing unique qualities that include *masame* elements typical of the Yamato tradition. Fine "hataraki" (activity marks) appear in the *kitae*, sometimes displaying an ethereal reflection like moonlight mirrored on a water surface—one of the greatest pleasures in appreciating Ko-Aoe.

The fine *nie* throughout the *kitae* is fine and uniform, creating a sharp, clear aesthetic overall. Moritsugu's *kitae* is especially orderly and beautiful, conveying the impression that a skilled blacksmith completely mastered the character of his materials. Such high-quality *kitae* is produced by a combination of the distinctive properties of the iron sand unique to Bitchu Province and the forging techniques transmitted through generations of the Aoe school—a distinctive beauty that cannot be readily reproduced elsewhere.

Characteristics of the Hamon: Fine Straight Edge and the Depth of Nie-Deki

Moritsugu's *hamon* consists primarily of fine, straight-edged patterns or gentle small undulations, centered on *nie-deki*. This *hamon*, seemingly plain at first glance, nevertheless possesses rich character upon close examination. The fine particles of *nie*, uniformly distributed across the entire edge, display a brilliance like silver sand laid out, and as the angle of light changes, complex expressions emerge within the edge. The *nioi-guchi* (scent boundary) is tight and deep, with fine *kinsuji* and *sunagarashi* (sand-flow marks) appearing at the boundary between the edge and *kitae*.

The distinctive depth of *nie-deki* in the *hamon* of Ko-Aoe displays a paradoxical richness: complex internal structure underlying the serene beauty of a simple straight edge. Avoiding flashiness yet deeply captivating to the viewer, this quality can be interpreted as embodying the spiritual essence of the samurai—the ideal of serene outward appearance yet possessing profound inner strength.

Moritsugu's Signature and Extant Works

Moritsugu's signature is inscribed either as the two characters "Moritsugu" or the four characters "Aoe Moritsugu," and the calligraphy displays forceful, well-ordered characters befitting a master craftsman. Multiple Important Cultural Properties and Important Art Objects by Moritsugu have been confirmed to exist and are highly regarded as representative works of Ko-Aoe. The *tachi* by Moritsugu that have been transmitted to various museums and shrines all clearly exhibit the distinctive *kitae* and *hamon* of Ko-Aoe and possess high value as teaching materials for Japanese sword appreciation. Particularly renowned among his works are the Important Cultural Property *tachi* transmitted throughout various regions, which, in their excellent preservation and superior quality, vividly convey the beauty of Ko-Aoe to the present day. To encounter a sword by Moritsugu is a precious opportunity to experience firsthand the diversity and profound depth of western Japanese sword culture that flourished in Bizen and Bitchu.

The Historical Position of the Aoe School and the Significance of Moritsugu

The Aoe school, among the five major systems of the Bizen tradition (the three Bizen provinces—Bizen, Bitchu, and Bingo—and their swordsmith communities), was a school that, while maintaining an independent technical system distinct from the mainstream of Bizen, made important contributions to Japanese sword culture as a whole during the Kamakura period. As a representative of its golden age, Moritsugu bore an important role alongside Ichimonji and Osafune in the sword culture of the Bizen region. At the Tōken-za, Moritsugu is presented as a master craftsman who embodied the unique world of beauty created by the interplay of Ko-Aoe's sumihada and profound *nie-deki* *hamon*. The beauty of Ko-Aoe, seemingly modest at first glance yet deepening with further viewing, represents the very essence of the supreme pleasure of Japanese sword appreciation, and Moritsugu's works stand as one of its highest peaks.

The Materials of the Aoe School and the Natural Environment of Bitchu

Behind the Aoe school's creation of distinctive *kitae* beauty lay the unique natural environment and material conditions of Bitchu Province. The Takahashi River basin, which flows through Bizen and Bitchu, contained abundant high-quality iron sand, and it is believed that the chemical composition of this iron sand significantly influenced the distinctive color and texture of the *kitae* of Ko-Aoe. The iron sand of Bitchu, with its subtly different composition from that of Bizen, produced distinctive surface patterns and reflections during the forging process. Moreover, the charcoal of Bitchu possessed distinctive burning characteristics, which are said to have influenced how the *nie* and *nioi* appeared during quenching.

Moritsugu completely understood these material conditions and established forging and quenching techniques that maximized their potential. The beauty of the resulting "sumihada" can be said to be a miraculous product born from the fortunate meeting of materials and technique. Moritsugu's works eloquently attest that the beauty of the Japanese sword is not merely a product of craftsmanship, but a comprehensive cultural expression in which land, materials, technique, and the spirit of the age are unified. When standing before one of Moritsugu's *tachi*, exceeding seventy centimeters in length and in excellent condition of preservation, it is said that the viewer often loses track of time and is drawn into this ethereal world of beauty. The sword of Aoe Moritsugu is one of the most silent yet most profound witnesses to the fact that the Japanese sword transcends mere weaponry to become a work of art.