德川家康所主導的「五人組」制度，在歷史上更準確的名稱其實是「五大老」，這並非江戶時代用於基層社會控制的五人連坐制度，而是豐臣政權末期為維持中央政權穩定所設立的最高權力合議機構。該制度最早形成於豐臣秀吉晚年，並在其去世後正式運作，名義上是為了共同輔佐年幼的繼承人豐臣秀賴，實際上卻成為權力鬥爭的舞台，最終也成德川家康奪取天下的重要過渡工具。

在制度設計上，五大老由當時實力最雄厚、領地最廣的五位大名組成，藉由勢力平衡來互相牽制，避免任何一方獨大。德川家康以關東地區高達二百五十六萬石的龐大封地，成為五大老中實力最為突出的核心人物；前田利家坐鎮加賀，擁有八十三萬石，被視為唯一能在政治與軍事上制衡家康的重要支柱；毛利輝元掌控安藝一帶，石高逾一百二十萬；上杉景勝鎮守會津，石高約一百二十萬；宇喜多秀家則以備前為根據地，石高約五十七萬。這樣的配置在紙面上看似平衡，實際上卻極度仰賴前田利家的存在來抑制家康的擴張野心。

1598年豐臣秀吉去世後，五大老與五奉行共同執掌政務，形成表面上的集體領導體制。然而制度的脆弱性很快顯現。1599年前田利家病逝後，原本的權力制衡瞬間崩解，德川家康的政治與軍事影響力開始迅速失控擴張。他透過聯姻、拉攏諸侯與調整封地等手段，不斷削弱其他大老的實質力量，使五大老制度逐漸流於形式。

這種失衡最終在1600年的關原之戰中徹底爆發。以德川家康為首的東軍擊潰由宇喜多秀家名義領導的西軍，毛利輝元與上杉景勝等勢力遭到嚴重削弱或被迫退居地方。關原之戰後，五大老作為集體決策機構已名存實亡，制度在事實上宣告瓦解，豐臣政權也進入不可逆的衰亡階段。

從歷史意義來看，五大老制度原本是豐臣秀吉為確保家族政權延續而設下的安全機制，試圖透過權力分散來防止內部崩潰。然而結果卻適得其反，這套制度不但未能阻止德川家康坐大，反而在過渡期內為他提供合法介入中央政務、整合諸侯勢力的舞台。最終，家康在制度瓦解後順勢奪權，並於1603年建立江戶幕府，正式開啟長達兩百六十餘年的德川統治時代。

The system led by Tokugawa Ieyasu that is sometimes referred to as a “five-person group” is, in historical terms, more accurately known as the Council of Five Elders. This was not the Edo-period grassroots mutual-responsibility system, but rather a supreme collective governing body established in the final years of Toyotomi Hideyoshi’s rule to stabilize central authority. Formed late in Hideyoshi’s life and put into effect after his death, the council was nominally intended to jointly support the young heir Toyotomi Hideyori. In reality, it quickly became an arena for power struggles and ultimately served as a transitional mechanism that enabled Tokugawa Ieyasu to seize control of the country.

In its design, the Council of Five Elders consisted of the five most powerful daimyo of the time, each commanding vast territories. The intention was to create a balance of power in which the elders would check one another and prevent any single figure from dominating the government. Tokugawa Ieyasu, with his enormous Kantō domain of roughly 2.56 million koku, was the most powerful and central figure among them. Maeda Toshiie, ruling Kaga with about 830,000 koku, was widely regarded as the only elder capable of politically and militarily restraining Ieyasu. Mōri Terumoto controlled Aki and surrounding regions with more than 1.2 million koku, Uesugi Kagekatsu governed Aizu with approximately 1.2 million koku, and Ukita Hideie held Bizen with around 574,000 koku. On paper, this configuration appeared balanced, but in practice it depended heavily on Maeda Toshiie’s presence to contain Ieyasu’s ambitions.

After Toyotomi Hideyoshi’s death in 1598, the Five Elders jointly governed state affairs alongside the Five Commissioners, creating the outward appearance of collective leadership. However, the system’s fragility soon became apparent. When Maeda Toshiie died in 1599, the carefully constructed balance of power collapsed almost overnight. Tokugawa Ieyasu’s political and military influence expanded rapidly, as he used marriages, alliances with other daimyo, and strategic adjustments of fiefs to weaken the remaining elders. As a result, the Council of Five Elders gradually became little more than a formality.

This imbalance ultimately erupted into open conflict at the Battle of Sekigahara in 1600. The Eastern Army led by Tokugawa Ieyasu defeated the Western Army, nominally headed by Ukita Hideie. The power of figures such as Mōri Terumoto and Uesugi Kagekatsu was severely diminished or pushed back into regional confines. After Sekigahara, the Council of Five Elders had effectively lost all real authority, and the system was dissolved in practice. At the same time, the Toyotomi regime entered an irreversible decline.

In historical perspective, the Council of Five Elders was originally conceived by Toyotomi Hideyoshi as a safeguard to ensure the survival of his family’s rule, using dispersed authority to prevent internal collapse. Ironically, it produced the opposite outcome. Rather than restraining Tokugawa Ieyasu, the system provided him with a legitimate platform during the transitional period to intervene in central governance and consolidate the power of the daimyo. Following the collapse of the council, Ieyasu moved decisively to seize authority, and in 1603 he established the Tokugawa shogunate, ushering in more than 260 years of Tokugawa rule over Japan.