expression
in spite of; despite; although
Used in the pattern 〜にもかかわらず to mean 'in spite of ~' or 'despite ~'. Often follows a noun, na-adjective stem, or plain form of a verb/i-adjective. The にも is usually present but may be omitted in casual speech.
雨にもかかわらず、多くの人が集まった。
Despite the rain, many people gathered.
彼は若いにもかかわらず、とても落ち着いている。
Although he is young, he is very composed.
expression
regardless of; irrespective of
Used in the pattern 〜にかかわらず to mean 'regardless of ~' or 'without being affected by ~'. Often follows nouns indicating difference, such as 年齢, 性別, 天候, or contrasting pairs like 晴雨. The に is essential here.
このイベントは年齢にかかわらず参加できます。
This event is open to participants regardless of age.
天候にかかわらず、試合は行われます。
The match will be held irrespective of the weather.
This is the full fixed phrase for 'despite', including the particle にも. かかわらず alone is the continuative form of 関わる, but in modern Japanese it is almost always used with に or にも.
The pattern for 'regardless of', using に instead of にも. The choice between にも and に changes the meaning from concessive ('despite') to unconditional ('regardless').
Derived from the negative continuative form of the verb 関わる (かかわる, 'to be involved/affected'), literally meaning 'without being involved/affected'. The modern grammaticalized usage as a conjunction-like expression developed from this literal sense.