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People group profile · PG009782

The Big Sepik of Papua New Guinea

The Big Sepik of Papua New Guinea, numbering about 19,000 people, are No Longer Unreached. They are an indigenous ethnic group of Papua New Guinea.

They are an indigenous people in the New Guinea people cluster of the Pacific Islander Peoples. Their primary religion is Roman Catholicism, and they primarily speak Iatmul.

Pray for the Big SepikPrint profile

AI-generated illustration representing the Big Sepik people
AI-generated illustration, not a photograph. Photo by Google. (2025). Image generated by Gemini 2.5 Flash: Big Sepik

Fast facts

Country
Papua New Guinea
Population
19,000
Affinity group
Asian Pacific Rim Peoples
People cluster
New Guinea
Primary language
Iatmul (ian)
Primary religion
Roman Catholicism
Strategic Progress Index ?
No Longer Unreached
Evangelical
5% or Greater but Less than 10%
GSEC ?
5% or Greater but Less than 10% Evangelical
Lostness priority ?
Marginally Reached People Group
Region
Melanesia, Oceania

Where they live

Gospel status

The Big Sepik are No Longer Unreached, which means 2% or more are evangelical Christians. In GSEC terms, this people group is greater than or equal to 5% evangelical.

  • Congregations exist Yes
  • Church planting in the last two years No Churches Planted

Next steps for the Big Sepik

  • Pray for the churches among this group to grow in faithfulness and maturity
  • Equip believers to reach the unreached peoples around them
  • Send out laborers from this people to the nations

Primary religion

Roman Catholicism · Christianity

73% adherents

Primary language

Iatmul · Ndu family

65% speak Iatmul

Gospel resources in Iatmul

  • Bible available, published 2013
  • JESUS Film not available
  • Radio programs not available
  • Gospel recordings available
  • Audio resources available
  • Bible stories not available

Bibles

Find more at the JESUS Film Project, Bible.com and Faith Comes by Hearing.

Pray for the Big Sepik

  1. 2 Timothy 2:2. Pray for faithful local leaders who will teach others, so that the church multiplies.
  2. Ephesians 5:8. Pray that those walking in darkness will turn to the light and live as children of light.
  3. Romans 10:14–15. Ask God to send messengers, so that people can hear, believe and call on the name of the Lord.
  4. Matthew 9:37–38. Ask the Lord of the harvest to send out laborers into his harvest field.

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