Image copyright Vilayat Dagestan website Image caption Islamic State Militants in Yemen in their first video

The Islamic State (IS) group has forged links with militants from Nigeria to Pakistan, embracing regional franchises that have pledged allegiance to the group.

The latest group to sign up is based in the republics of Russia's North Caucasus, led by a Dagestan jihadist commander who defected to IS from the al-Qaeda-aligned rebel movement known as the Caucasus Emirate.

The first new branches beyond the group's strongholds in Syria and Iraq were announced by IS leader Abu-Bakr al-Baghdadi in November last year when he accepted pledges of allegiance from jihadists in Egypt, Libya, Algeria, Yemen and Saudi Arabia.

Some of those pledges came from existing groups which went on to re-brand themselves as new IS "provinces", or wilayat, such as the Egyptian Ansar Bayt al-Maqdis and Algeria's Jund al-Khilafah.

The most active branches have been those in Libya and Egypt, which have tapped into the IS media network to publish a steady flow of propaganda, highlighting attacks and publicising their attempts at governance.

Others have had a low profile. For example, the IS franchises in Algeria and Saudi Arabia have claimed only a few isolated attacks and there is no sign that the group has a strong presence there.

But the impact of the IS expansion has nevertheless been felt by its jihadist rivals in al-Qaeda, which has branches in many of the areas IS has moved into, and in-fighting has broken out in several areas.

Egypt

The IS branch in Egypt, Sinai Province, was essentially a re-branding of an existing group known as Ansar Beit al-Maqdis, which first emerged in 2011 in the wake of the Egyptian revolution.

Image copyright BBC Monitoring Image caption Logo for IS in Sinai based in Egypt

Before the pledge by Nigeria's Boko Haram in March, Sinai was the highest-profile established jihadist group to merge with IS and has kept up the tempo of its operations following the change in November.

The group swiftly changed its name and re-branded its media to reflect the new affiliation, adopting a new logo reminiscent of IS branches in Syria and Iraq.

Its activities are focused on the Sinai Peninsula (where it launched a deadly attack on soldiers on 2 April) but it has also claimed attacks in Cairo and Egypt's western desert, suggesting it might have some ability to link up with the IS branch in Libya.

Full profile: Ansar Beit al-Maqdis (Sinai)

Libya

The Libyan branch of IS has been the most active since it was formally embraced in November and its propaganda output has most closely resembled that of IS branches in Syria and Iraq.

Three distinct Libyan IS "provinces" were announced in November - Barqah in the east, Tripoli in the west and Fazzan in the south.

Image copyright BBC Monitoring Image caption This still from a video promotes another IS in Libya group, with this one active in Tripoli

Since then, most activity has been centred on the country's coastal strip, reflected in a steady stream of propaganda highlighting the group's attempts at governance alongside brutal attacks and executions.

Image copyright BBC Monitoring Image caption This IS propaganda map claims swathes of Libyan territory for the group

The branch's highest-profile operations have taken place in the west - the 27 January attack on the Corinthia Hotel in Tripoli, which left five foreigners dead, and the beheading of Egyptian Coptic Christians on a beach apparently near Sirte.

It claimed to have taken full control of Sirte in early June.

But the group has been drawn increasingly into conflicts with other jihadist and Islamist forces in Libya, including those aligned with al-Qaeda.

Algeria

Little has been heard of the Algerian branch of IS since the pledge of allegiance from Jund al-Khilafah was accepted by Baghdadi in November.

Image copyright Twitter Image caption Logo for IS in Algeria

The group, which broke away from al-Qaeda's North Africa branch (AQIM) last year, later restyled itself as the Algeria Province of IS.

The group rose to prominence in September when it beheaded French tourist Herve Gourdel.

But it has been largely silent since then, failing to comment on reports that its leader Khalid Abu-Sulayman (aka Abdelmalek Gouri) was killed by Algerian forces in December.

It has claimed a few attacks, but no significant activities.

Yemen and Saudi Arabia

IS drew the ire of al-Qaeda's Yemen branch (AQAP) when Al-Baghdadi unilaterally announced new "provinces" in Yemen and Saudi Arabia in November.

Those branches have since claimed attacks in both countries, including a devastating series of attacks in March against mosques in the Yemeni capital which left more than 130 people dead.

Image copyright Reuters Image caption Two mosques were packed for Friday prayers when the bombers struck

Opening up shop in the Arabian Peninsula represents a symbolic challenge to al-Qaeda, which is competing for ascendancy in the leadership of the global jihad.

It could also in time lead to an open conflict between IS and AQAP.

Afghanistan-Pakistan

The new Afghanistan-Pakistan branch, led by former Pakistan Taleban commander Hafiz Said Khan, was the first franchise to be formally announced by IS following the November flurry of allegiances.

In January, Khan appeared in a video which showed 10 jihadist commanders from Afghanistan and Pakistan pledging allegiance to IS under his local leadership.

Since then it has claimed attacks in both Afghanistan and Pakistan, including the 13 May bus attack targeting Ismaili Shia Muslims in Karachi.

The new branch has taken the name Khorasan Province, after the historical term jihadists use to refer to the region, and covers Afghanistan, Pakistan and "other nearby lands", according to IS.

The move amounts to another major challenge to al-Qaeda and the Taleban, which have been the main jihadist operators in the region.

Image copyright BBC Monitoring Image caption A still from a propaganda video showing the leader of IS in Khorasan, based around Afghanistan and Pakistan

Open conflict has recently broken out between IS and the Afghan Taleban, which IS has accused of being agents of Pakistani intelligence.

Nigeria

Boko Haram's high profile pledge of allegiance in March was widely trumpeted by IS, which is now referring to the group as its "West Africa Province".

Image copyright AFP Image caption Boko Haram has been fighting an insurgency to create an Islamic state in northern Nigeria since 2009

Before the announcement, there had been signs in Boko Haram's propaganda output of growing IS influence on the Nigerian movement, whose ideology and harsh practices mirror those of IS itself.

Since March, the group has continued claiming attacks and releasing videos, but its leader Abubakar Shekau has failed to make any appearances.

Tunisia

A pledge of allegiance by jihadists in Tunisia was promoted by IS in May, two months after the group claimed credit for the 18 March attack on the Bardo Museum in the capital Tunis.

It followed the same format as other pledges of allegiance which have been followed up by IS leadership statements formally embracing the new branches.

But an official branch or province in Tunisia has yet to be formally declared, apparently because the local franchise has yet to organise itself properly.

Caucasus

The Caucasus is the latest jihadist front to be claimed by IS, encroaching on the domain of the al-Qaeda-aligned Caucasus Emirate.

IS announced on 23 June that its leader Abu-Bakr al-Baghdadi had accepted a pledge of allegiance from militants in the Russian republics of Chechnya, Dagestan, Ingushetia and Kabardino-Balkaria.

Image copyright BBC Monitoring Image caption The new leader of IS's Caucasus branch, Rustam Aselderov aka Abu Mukhammad Kadarsky

Dagestan rebel leader Rustam Aselderov (Abu Mukhammad Kadarsky) has been appointed as the local IS leader for the Caucasus, which is now being referred to as IS's "Caucasus Province".

Aselderov had been a senior figure in the Caucasus Emirate, which may now struggle to survive as an independent entity.

Other regions

IS has now expanded into most areas where jihadist groups have a presence, with the notable exceptions of south-east Asia as well as east Africa, the latter region being dominated by the Somali al-Qaeda-affiliated group Al-Shabab.

IS acknowledged in November last year that groups in Indonesia and the Philippines had also pledged allegiance and that IS had accepted them.

But it said further conditions needed to be met before new "provinces" were formally announced.

BBC Monitoring reports and analyses news from TV, radio, web and print media around the world. You can follow BBC Monitoring on Twitter and Facebook.