dynasticAlliance

Given a predicate that represents a relationship or action between entities, generate a one-sentence description explaining its meaning.  
# Instructions
Focus on describing the relationship, not the entities themselves. 
# Response Format
Begin the description with \' Indicates...\'

Predicate: dynasticAlliance

Indicates a formal union or cooperative relationship established between ruling families or dynasties, typically through marriage or treaty, to secure mutual political or strategic advantage.