Taglung Kagyu
The Shangpa Kagyu school (shangs pa bka' brgyud) developed independently and is not counted among the Four Greater and Eight Lesser Dagpo Kagyu schools which originated with Tilopa, Naropa and Marpa and which passed through Milarepa and Gampopa, even though many of its teachings and practices have been assimilated into, and continue to be transmitted by the Karma Kagyu school today. For more detailed information check the excellent "Shangpa Network" website (see external link below).
As a matter of fact "Kagyu" (bka' brgyud) simply means "oral transmission". Therefore, any lineage that has transmitted its teachings orally, could call itself a "Kagyu" lineage. Nowadays the lineages that are associated with Marpa and Gampopa are mostly called "Kagyu", Marpa Kagyu or Dagpo Kagyu, and the Shangpa Kagyu are often erroneously considered part of that group of lineages.
The Shangpa Kagyu is one of the eight great practice lineages (sgrub brgyud shing rta brgyad) of the Tibetan buddhist tradition and exists as an unbroken lineage to the present day. Its most prominent lineage holders outside of Tibet were the previous Kalu Rinpoche (1904-1989) and Bokar Rinpoche (1940-2004). The present main lineage holder is the second Kalu Rinpoche (b.1990). But other masters hold this lineage as well, like H.E. the present 12th Tai Situpa or the Vajra Master Ven. Tenga Rinpoche of Benchen monastery, both of whom will give the transmissions of the Shangpa Kagyu Lineage this year (2009) in their respective monasteries (see links below).
The lineage was established by the great scholar and accomplished master Khedrub Khyungpo Naljor (11/12th cent.), who travelled several times to India and studied under many masters, predominantly under the two great female Mahasiddhas Niguma and Sukhasiddhi, and under Maitripa and Rahula, who also happened to be one of the early teachers of the great Atisha. Khyungpo Naljor hailed from the same family-clan, the clan of Khyungpo, as Jetsun Milarepa. The school, like many others, was named after the location where its founder eventually settled, the valley of Shang in Central Tibet, not far north of the town of Shigatse (gzhis ka rtse). The teachings and practices special to the Shangpa Kagyu school are what is known as "The Five Golden Dharmas of the Shangpa" (shangs pa gser chos lnga). They are likened to a tree with its roots, trunk, branches, flowers and fruits.
"The Five Golden Dharmas of the Shangpa" are:
The roots: the Six Doctrines of Niguma (rtsa ba ni gu chos drug)
The trunk: the Mahamudra of the Amulet Box (sdong po phyag chen ga'u ma)
The branches: the Three Carry-Overs (of phenomena and appearances) onto the path (yal kha lam khyer rnam gsum)
The flowers: the White and Red Forms of the Dakini (me tog mkha' spyod dkar dmar)
The fruits: the Deathlessness and Non-deviation of Mindnature ('bras bu 'chi med chugs med)
The first seven masters, from the Dharmakayabuddha Vajradhara until Choje Sangye Tonpa, are known as the "Seven Jewels" of the Shangpa Kagyu. Curiously, Sukhasiddhi is not counted among these, otherwise there would be eight. Among these seven, the full lineage transmission was passed on from the master to only a single disciple. After that, it was spread much more widely. Sangye Tonpa (sangs rgyas ston pa brtson 'grus seng ge - 1213-1285) had two main students, Khedrub Tsangma Shangton (mkhas grub gtsang ma shangs ston) and Khetsun Shonu Drub (mkhas btsun gzhon nu grub). From thereon onwards, the Shangpa teachings continued to be transmitted through four main lineages. The Jonang transmission of the Shangpa teachings, as well as the Thanglug (thang lugs) and Jagpa ('jag pa) lineages, originated with Shangton, whereas the Nyangme Samding (nyang smad bsam sding) lineage originated with Shonu Drub. See my Shangpa Lineages Outline.
However, none of these lineages, except for the Jonang who were already well established, established themselves with big institutions like monasteries or monastic universities. The Shangpa Kagyu as a lineage have always remained fairly unobtrusive, mainly because most of its principal lineage holders chose to live as hidden yogins, thus avoiding all the many responsibilities that come with running monasteries and affiliated institutions. In this way most Shangpa masters could devote themselves to many years of meditation in solitude.
Many of the Shangpa teachings were also integrated into other schools. It is therefore not surprising that we find teachings and practices of the Shangpa even in the Sakya and Gelug schools. Jagchen Jampa Pal (1310-1391) for instance, a prominent holder of the Jagpa tradition of the Shangpa teachings, was one of the teachers of Tsongkhapa Lobsang Dragpa (1357-1419). Another great master of this particular Shangpa lineage was Lapchi Namkha Gyaltsen (la phyi nam mkha' rgyal mtshan, 1372-1437), who was also a lineage holder of the Sakya, Karma Kagyu and Drikung Kagyu traditions. Jetsun Kunga Drolchog (1507-1566), a great Sakya and Jonang master, was very fond of the Six Doctrines of Niguma and is known to have taught them many times to many masters from all sorts of schools and traditions.
The various existing streams of Shangpa transmissions were all received by Kongtrul Lodro Thaye and then passed on by him. He received the Tanglug lineage from the great Jamyang Khyentse Wangpo. The Jonang lineage of the Shangpa teachings came to Kongtrul through Karma Shenpen Ozer (karma gshan phan 'od zer), who was also known as Lama Karma Norbu, about whom we know virtually nothing.
I do hope that people more familiar with the Shangpa Kagyu school than I, will correct and expand upon my scribblings soon!