The Late Formative, as I define it here, refers to the period of time between the rise of the Pukara polity in the northern Titicaca Basin and the beginning of the classic Tiwanaku period in the South. The rise of Pukara is usually dated to around 200 B.C. (see [Mujica 1987], also [Chávez 1988]). This beginning of this period coincides neatly with the transition from Late Chiripa to Kalasasaya ceramics in the South, which I have placed at 250 B.C. (see Chapter 6 and below).
In the southern Titicaca Basin, the Late Formative period saw two major political and cultural developments. The first of these was the rise of the first multi-community polities, around 250 B.C. At this time the site of Kala Uyuni (T-232) on the Taraco Peninsula came to dominate its immediate neighbors. The resulting social formation, the Taraco Peninsula polity, was characterized by a three-tier site size hierarchy. Its formation coincided with that of Pukara in the northern basin, and apparently also with that of Tiwanaku in the Tiwanaku Valley. The Taraco Peninsula Polity - identified her for the first time - was probably roughly the same size as the Tiwanaku polity during the earlier part of the Late Formative. The formation of an unoccupied buffer zone between the Taraco Peninsula and Tiwanaku polities would seem to indicate that they were competitors. The Taraco Peninsula polity existed from 250 B.C. to approximately 300 A.D. This period will be referred to as the Late Formative 1 (LF1).
Around 300 A.D. the Tiwanaku polity, heretofore more or less an equal
competitor of the Taraco Peninsula polity, became suddenly dominant.
Over the following two centuries the site of Tiwanaku rapidly grew
to cover approximately 1 km
. Ponce has aptly termed this period
the ``estadio urbano temprano,'' the early urban stage of Tiwanaku
([Ponce Sangines 1981]). I refer to it here as the Late Formative 2 (LF2).
The drastic increase in the rate of population growth at Tiwanaku
itself was paralleled by a more or less radical depopulation of its
hinterland. Though the radius of Tiwanaku's initial political expansion
early in the LF2 is poorly defined, the Taraco Peninsula definitely
fell within its orbit at this time. The population of the peninsula
as a whole decreased during this period for the first time in the
occupational history of the region. This population decline was near-universal
on the peninsula, with only a very few sites remaining constant or
experiencing very slight growth. This flow of population from the
Taraco Peninsula - and other adjacent areas - into Tiwanaku is one
of the most interesting and perplexing events in Titicaca Basin prehistory,
and one of the most important for our understanding of Tiwanaku state
formation. It will be considered in as much detail as the limited
data at our disposal allow. The LF2 ends with the appearance of classic
Tiwanaku ceramics throughout the Titicaca Basin around 500 A.D.