The hippocampus plays a critical role in memory for sequences of events. This study shows that hippocampal lesions in rats impair their ability to remember the sequential order of odors, despite intact recognition of recently encountered odors. These findings support the hypothesis that hippocampal networks are essential for associating sequential events that form parts of episodic memories. In humans, the hippocampus is crucial for recalling specific personal experiences. However, it is challenging to assess this in animals due to their inability to report experiences explicitly. Nevertheless, features of episodic memory, including temporal, spatial, and situational context, can be studied in animals. Recent theoretical models emphasize the potential role of the hippocampus in representing the sequential ordering of events in a unique behavioral episode. Hippocampal damage impairs memory for the order of spatial locations visited, but there has been no conclusive evidence for a role in sequence memory specifically. Recognition and working memory for nonspatial stimuli depend on associating events across time. However, selective hippocampal damage has only modest or no impairment in recognition or working memory for nonspatial cues. The study directly compared memory for the sequential order of events with memory for the prior occurrence of events independent of their order. Rats with hippocampal lesions performed poorly on sequential order tasks, indicating a specific impairment in remembering the order of events. In contrast, they performed well on recognition tasks, suggesting that they could recognize odors even without remembering their order. This indicates that the hippocampus is essential for remembering the order of events but not for recognizing individual items. The study also found that hippocampal damage did not affect the ability to recognize recently presented items, but impaired the ability to remember the order of events. The results highlight the critical role of the hippocampus in memory for sequential order, independent of familiarity and spatial representation. The study used a variety of tasks to assess memory for sequential order and recognition, and found that hippocampal damage impaired sequential order memory but not recognition memory. These findings support the view that the hippocampus plays a specific and fundamental role in memory for sequences of events that compose unique episodes. The study also suggests that the hippocampus contributes to sequence memory independently of spatial context. The results have implications for understanding the role of the hippocampus in memory and for developing animal models of amnesia.The hippocampus plays a critical role in memory for sequences of events. This study shows that hippocampal lesions in rats impair their ability to remember the sequential order of odors, despite intact recognition of recently encountered odors. These findings support the hypothesis that hippocampal networks are essential for associating sequential events that form parts of episodic memories. In humans, the hippocampus is crucial for recalling specific personal experiences. However, it is challenging to assess this in animals due to their inability to report experiences explicitly. Nevertheless, features of episodic memory, including temporal, spatial, and situational context, can be studied in animals. Recent theoretical models emphasize the potential role of the hippocampus in representing the sequential ordering of events in a unique behavioral episode. Hippocampal damage impairs memory for the order of spatial locations visited, but there has been no conclusive evidence for a role in sequence memory specifically. Recognition and working memory for nonspatial stimuli depend on associating events across time. However, selective hippocampal damage has only modest or no impairment in recognition or working memory for nonspatial cues. The study directly compared memory for the sequential order of events with memory for the prior occurrence of events independent of their order. Rats with hippocampal lesions performed poorly on sequential order tasks, indicating a specific impairment in remembering the order of events. In contrast, they performed well on recognition tasks, suggesting that they could recognize odors even without remembering their order. This indicates that the hippocampus is essential for remembering the order of events but not for recognizing individual items. The study also found that hippocampal damage did not affect the ability to recognize recently presented items, but impaired the ability to remember the order of events. The results highlight the critical role of the hippocampus in memory for sequential order, independent of familiarity and spatial representation. The study used a variety of tasks to assess memory for sequential order and recognition, and found that hippocampal damage impaired sequential order memory but not recognition memory. These findings support the view that the hippocampus plays a specific and fundamental role in memory for sequences of events that compose unique episodes. The study also suggests that the hippocampus contributes to sequence memory independently of spatial context. The results have implications for understanding the role of the hippocampus in memory and for developing animal models of amnesia.