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Earthquakes can be dynamically triggered by the passing waves of other distant events. The frequent occurrence of dynamic triggering offers tangible hope in revealing earthquake nucleation processes. However, the physical mechanisms behind earthquake dynamic triggering have remained unclear, and contributions of competing hypotheses are challenging to isolate with individual case studies. To gain a systematic understanding of the spatiotemporal patterns of dynamic triggering, we investigate the phenomenon in southern California from 2008 to 2017. We use the Quake Template Matching catalog and an approach that does not assume an earthquake occurrence distribution. We develop a new set of statistics to examine the significance of seismicity‐rate changes as well as moment‐release changes. Our results show that up to 70% of 1,388 global M ≥ 6 events may have triggered earthquakes in southern California. The triggered seismicity often occurred several hours after the passing seismic waves. The Salton Sea Geothermal Field, San Jacinto fault, and Coso Geothermal Field are particularly prone to triggering. Although adjacent fault segments can be triggered by the same earthquakes, the majority of triggered earthquakes seem to be uncorrelated, suggesting that the process is primarily governed by local conditions. Further, the occurrence of dynamic triggering does not seem to correlate with ground motion (e.g., peak ground velocity) at the triggered sites. These observations indicate that nonlinear processes may have primarily regulated the dynamic triggering cases. Plain Language Summary: Earthquakes interact with each other, such as mainshocks triggering nearby aftershocks. Earthquake dynamic triggering is a type of interaction where seismic waves from an earthquake trigger other earthquakes beyond several fault lengths, and sometimes, up to thousands of kilometers away. Triggered earthquakes may occur upon the arrival of the seismic waves but may also be delayed hours after the wave passage, suggesting the involvement of time‐dependent processes. Identifying delayed cases relies on robust measures of seismicity‐rate changes. Here we present a new method that can identify triggering cases without many assumptions. We find that earthquakes in southern California are frequently triggered by distant earthquakes around the globe, and the triggered earthquakes tend to cluster in space and time. We also find that the triggering incidences do not seem to correlate with the seismic wave characteristics of the distant earthquakes. Our findings suggest that dynamically triggered earthquakes in southern California are likely caused by time‐dependent, local complex processes. Key Points: Earthquake dynamic triggering is ubiquitous in southern CaliforniaTriggered earthquakes are frequently associated with significant moment‐release anomalies and are likely controlled by local processesOur procedure does not assume that seismicity follows a Poissonian distribution when identifying dynamic triggering [ABSTRACT FROM AUTHOR]