Were the Late Bronze Age destructions synchronous or sequential?

The question

Were the destructions and palace collapses of the late-bronze-age-collapse tightly clustered in a "wave" within a few decades of ~1200–1180 BCE, or were they spread over a longer timeline (Late Helladic IIIB to LH IIIC, c. 1315–1050 BCE) with destructions occurring sequentially as one civilization's collapse triggered the next?

Why it matters

The synchronicity question gates which causal frame is most explanatory:

• If synchronous (tightly clustered): a strong external trigger (climate, plague, mass migration) is the most parsimonious explanation. The "perfect storm" framing of lba-multi-stressor-collapse-chain reads as a single causal cascade.
• If sequential: cascading internal-vulnerability dynamics gain weight. joseph-tainter-style complexity-collapse readings become more competitive against externally-driven climate readings.

Current state

The popular narrative treats destructions as effectively simultaneous within a few decades. The careful academic framing is more bounded:

• From 2026-05-13-autoresearch-bronze-age-collapse-causes-scholarly-consensus: "this period of dissolution begins in the Late Helladic IIIB (1315-1190 BCE) and is complete by the end of the LH IIIC (1050 BCE), indicating a longer timeframe than the 'few decades' characterization." The Mycenaean palatial transition spans ~250 years end-to-end.
• From 2026-05-13-autoresearch-bronze-age-collapse-causes-scholarly-consensus (Bret Devereaux, ACOUP January 2026): the destructions occurred in "very rough sequence" across regions rather than simultaneously; chronology remains "tricky"; "in many cases my sense is the chronology is more complex" than the traditional "wave" model suggests.
• From 2026-05-13-autoresearch-bronze-age-collapse-causes-scholarly-consensus (Devereaux 2026): "the scale of the collapse remains something of a moving target as we excavate more sites."
• jesse-millek's 2023 audit (61% of claimed destructions misdated/false) further fragments the synchronicity narrative — a destruction event misdated to 1200 BCE that actually occurred decades earlier or later removes a data point from the "wave" pattern.

What would close this

• High-resolution dating refinement on the confirmed ~59 destruction events (per Millek). If they cluster tightly within a 30-year band, "synchronous" wins; if they spread across 100+ years, "sequential" wins.
• Better Bayesian frameworks for archaeological dating uncertainty.
• More excavation at second-tier sites in less-studied regions (the Aegean and Levant are well-studied; Anatolian, Cypriot, and Mesopotamian peripheries less so).

Related

• late-bronze-age-collapse
• lba-multi-stressor-collapse-chain
• jesse-millek