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The hippocampus is a central node within the hippocampal-cortical autobiographical memory network (AMN) supporting the formation, consolidation, and retrieval of episodic memories, including autobiographical memories (AMs). Controversy remains regarding the temporal role the hippocampus plays in lifetime AM retrieval. Previously, leucine-rich glioma-inactivated-1-limbic encephalitis (LGI1-LE) has been shown to result in extensive autobiographical amnesia (and focal hippocampal pathology). Here, we attempted to replicate this pattern in a new cohort of participants (compared to age- and neuropsychologically-matched healthy controls) in the chronic phase of treated LGI1-LE using the Autobiographical Interview, a structured measure that quantifies the episodic and semantic details of AMs. We demonstrated that 18 participants with LGI1-LE had impaired lifetime AM performance, replicating previous findings. Following this, we combined 18 members from each cohort with one memory per decade over a period of at least six decades to undertake a more granular decade-by-decade assessment of AM performance. These data demonstrated impaired decade-by-decade AM performance following LGI1-LE. These replicative and novel data demonstrate that LGI1-LE results in retrograde autobiographical amnesia across the lifetime and is at variance with a time-limited role of the human hippocampus in memory consolidation. We discuss the implications of these results for neurobiological models of episodic memory.joseph.zhou.20@ucl.ac.uk