赛德克，在赛德克语中意指“真正的人”，因其文化习俗与泰雅相似，自日本侵占台湾时期起，就一直被归属为泰雅的亚族，直至2008年4月才被确认为赛德克，成为台湾少数民族的第14个族群。
赛德克氏族发源于南投仁爱乡的浊水溪上游，并在此分成德克搭雅、都达、太鲁阁三个最早的社群。大约18世纪，这三个社群因为人口增加、土地不敷使用，各有一部份人翻越中央山脉分水岭，迁徙到花莲县境内，形成了居住在南投仁爱乡的西赛德克，以及居住在花莲县秀林、万荣、卓溪乡的东赛德克。而每一地方族群之下又各分成三个社群，总数共有六个社群。其中东赛德克德鲁固群已在2004年另划归为“太鲁阁”族群。
赛德克人的传统生活方式和习俗，是重视男猎女织的男女分工，也拥有纹面成年礼及严守祖灵禁忌等传统习俗。部落是最基本的自治单位，属于没有世袭头目的平权社会，由领导能力强的人出任部落领袖，狩猎、出草也由英勇的族人担任领袖。当遇到部落有重大事情时，则是由长老会议决策，部落组织对内具有保护功能，对外则负有与其它部落保持联络的责任，是一个同地域同盟共利的团体。
赛德克也拥有泰雅族群类似的兼有宗教和互助性质的“嘎嘎”团体，只是赛德克语称之为“嘎呀”。赛德克的嘎呀成员几乎都属同一部落，很少出现泰雅那种跨部落的情况。同一个嘎呀的成员之间，有共同从事祭祀、协助参与复仇、集体分摊赔偿的义务，而且“嘎呀”也可解释为部落的习惯法律或传统禁忌。
Sediq / Sejiq / Seediq
Sediq, Sejiq or Seediq refers to “true person” in the tribe’s native language. Due to similarities with the Atayal in terms of culture and customs, scholars originally defined the Sediq as a branch of the Atayal tribe. However, in April of 2008, the Sediq was recognized as Taiwan’s 14th official tribe.
The Sediq were originally located along the upper reaches of the Zhuoshui River in Renai Township of Nantou County. From there, they branched out into three groups: Tkdaya, Teuda and Truku. Around the 18th century, due to a growing population, some members of the Sediq tribe crossed the Central Mountain Range to arrive in present-day Hualien County. Those that remained in Renai Township were referred to as the western Sediq and those that resided in Hualien were referred to as the eastern Sediq. In 2004, the eastern Sediq were incorporated into the Truku.
Traditionally, the males hunted and the females wove cloth. The Sediq practiced facial tattooing as part of the coming-of-age rites and observed the taboos and lessons passed down from the ancestors. The society was based on equal rights and there was no chieftain system. Those with outstanding qualities were chosen to lead the village. Hunting and warring expeditions were led by the bravest warriors. If the village met with a major crisis the elders’ council would decide on a solution.
Similar to the “Gaga” of the Atayal tribe, the Sediq had a group, called the “Gaya” to oversee the religious practices and customs. The “Gaya” can also be interpreted to mean the common law or traditional taboos of the village.
